This session welcomes contributions on the following topics:
- Exploration and extraction of CRMs as primary resources.
- CRM recovery as by-products of common mineral exploitation.
- Revalorization of extractive waste facilities as secondary sources of CRMs.
- Technological innovations for the exploration, extraction, and (re)processing of minerals from primary deposits and EW.
- Technological advancements in sampling and characterization procedures for minerals and EW, aimed at improved resource evaluation and environmental impact assessment.
- Multiscale CRM exploration: innovative sensing technologies, automation, and modeling of primary and secondary resources.
- Environmental aspects of CRM extraction from primary resources.
- Environmental and geotechnical innovations for tackling challenges associated with EW facilities.
- The role of current regulations in driving innovative solutions and fostering responsible production of mined products including the extraction of CRMs.
- Role of economists, social scientists, legal scholars, psychologists, and policymakers in addressing the social and economic challenges of new and reactivated mines to promote a responsible and socially accepted mining sector.
- The role of AI and machine learning across the entire mining life cycle.
Orals: Wed, 6 May, 14:00–18:00 | Room -2.43
Lithium (Li) has become a critical and strategic metal owing to its distinctive physical and chemical properties and its wide range of applications, including batteries, ceramics, glass production, nuclear materials, and lubricating greases. Oilfield brines represent a significant alternative Li resource capable of meeting increasing global demand in the coming decades, and most petroliferous basins are known to contain Li-enriched formation waters. This study investigates the origin of Li in oilfield brines from actively producing fields operated by the Turkish Petroleum Company in southeastern Turkiye. Southeastern Anatolia, which hosts the main oil-producing fields of Turkiye, is located at the northern margin of the Arabian Plate and experienced Paleozoic epirogenic movements associated with the Caledonian and Hercynian orogenies. These tectonic events played a key role in shaping the regional structural framework, controlling basin architecture and long-term fluid pathways that governed the amount and origin of oilfield brines. The Ca, Na, and molar ratios of Cl/Br, Na/Cl, Ca/Mg and Ca/Sr in the brines indicate the influence of multiple diagenetic processes, including halite dissolution, dolomitization, albitization, and calcite or anhydrite cementation. The studied brines contain Li concentrations (up to 10 mg/L) and are characterized by relatively low B, Br, and Sr contents. The salinity of the brines within the sedimentary basins is primarily attributed to evaporation and/or evaporite dissolution. Minor contributions from halite dissolution are indicated by the moderate correlation between the molar Cl/Br and Na/Cl ratios. Furthermore, relatively strong relationships between Li concentration, salinity, and Cl/Br ratios support this interpretation. Trends observed in Ca/Mg and Ca/Sr molar ratios further suggest the occurrence of dolomitization and calcite recrystallization processes. Overall, these results indicate that further integrated studies are required to better constrain modes of occurrences of Li, highlighting the significance of oilfield brines in southeastern Turkiye.
How to cite: Doner, Z., Ünal, A., Ozdamar, S., Kumral, M., Sutcu, N. M., Billor, M. Z., Lee, M.-K., Zou, H., Bahtiyar, I., Eyeci, H., and Temel, R. O.: Lithium (Li) geochemistry of oilfield brines: An example from petroliferous basins in southeastern Turkiye, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-10640, https://doi.org/10.5194/egusphere-egu26-10640, 2026.
Recent advancements in green and sustainable technologies, particularly for decarbonisation and the energy transition, have led to a growing demand for Critical Raw Materials (CRMs). In response, the European Commission is encouraging exploration for economically viable CRMs deposits. The LREE-F-rich belt of the Roman Comagmatic Province (RCP; Washington, 1906) has emerged as a promising target (Mastrangelo, 1976; Stoppa et al., 2016, 2019), hosting key sites: the Pianciano deposit, which features a fluoritite–F-Ca carbonatite orebody, currently the largest underdeveloped fluorite resource in Western Europe, and the Santa Maria di Sala deposit, characterised by F-Ca carbonatite. Both deposits formed from carbothermal fluids derived from carbonatite magmas and exhibit interesting concentrations of LREEs (La, Ce, Pr, Nd) and barite, suggesting their potential for CRMs economically viable recovery.
Here we present the preliminary results of a comprehensive geological and geochemical survey carried out over these study areas, including the first detailed mapping of the Santa Maria di Sala deposit.
The Santa Maria di Sala deposit, which covers an area of approximately 2.5 km², formed in a shallow water basin, with paleosoils intercalations, lignite fragments and travertine beds or layers, suggesting a lacustrine environment. In its northern sector, the deposit is almost continuously exposed, most likely set on a single stratigraphic level, whereas in the southern sector it has a more heteropic character, intercalated with volcanic and fluvial deposits, and developed in at least two distinct series. The deposit is characterised by a very fine grain size, from 200 µm to <1 µm, and displays variable compositions and relative abundances of primary constituent minerals.
XRPD and SEM analyses of samples from Pianciano and Santa Maria di Sala deposits reveal that the dominant mineral phases in both deposits are fluorite (up to 90% in fluoritite and 50% in carbonatite), calcite, and barite, with subordinate apatite, clay minerals, (Pb, Mn)-carbonates, diopside, zeolites, spinel, rare microcline, zircon, garnet, vesuvianite, Fe-horneblende, and occasional Ce-wakefieldite, vanadinite and titanite.
XRF and ICP-MS dataindicate LREEs concentrations of ~1000–2700 ppm in fluoritites and ~200–800 ppm in carbonatites, hosted principally in apatite and Pb+Mn-carbonates which may contain ~0.5-4% of them.
Preliminary LREEs extraction tests using HCl or citric acid, under variable conditions of time, temperature, concentration and quantity of reagent, showed excellent extraction rates for carbonatites (up to 100%), and lower rates for fluoritites (up to 30%). Although the extraction rate from fluoritites is much lower, the amount of LREEs recovered with citric acid for a given mass of sample is broadly similar due to the higher initial concentration. Optimization of extraction protocols for more efficient LREEs recovery, especially for fluoritites, is ongoing.
How to cite: Sciamanna, L., Perna, M. G., Parlapiano, F., Rosatelli, G., Casarotto, B., Massironi, M., Stoppa, F., Valentini, L., and Nimis, P.: CRMs from the LREE-F-rich belt of the Roman Comagmatic Province (Central Italy) , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19153, 2026.
Strategic Raw Materials (SRMs) are fundamental to the development of energy‑transition technologies, and the European Union promotes domestic exploration through the Critical Raw Materials Act. In this context, the Emilia Romagna region (Northern Apennines) represents a promising area for SRM prospection owing to the presence of ultramafic ophiolitic sequences and volcanogenic massive sulfide (VMS) deposits associated with the External Ligurides Formation [1].
This study investigates SRM enrichment in river sediments influenced by variable mafic detrital contributions, integrating geochemical, mineralogical, and magnetic separation techniques. Bulk sediment characterization was carried out using X‑ray fluorescence (XRF) on glass beads and pressed powders, and inductively coupled plasma mass spectrometry (ICP‑MS) on acid‑digested samples to quantify major and trace elements.
Fine sand fractions were processed using a Frantz isodynamic magnetic separator to isolate magnetic and paramagnetic mineral concentrates. These separates were subsequently examined through scanning electron microscopy (SEM) to characterize ore minerals, identify SRM‑bearing phases, and evaluate their textural and compositional variability.
Trace‑element analyses of magnetic heavy‑mineral fractions were performed via ICP‑MS, with specific attention to elements of strategic relevance in this geological setting—namely chromium, nickel, manganese, zinc, and boron. These elements represent key targets due to their association with ultramafic lithologies, hydrothermal systems, and industrial applications linked to the energy transition.
Dragone Creek, Taro River, Nure River, and Trebbia River were selected to represent different mafic inputs and sediment‑transport dynamics. Preliminary results reveal distinct SRM concentration patterns across the catchments, with higher Cr and Ni contents in basins draining ophiolitic units (bulk concentrations up to 1000 ppm), and variable Mn, Zn, and B enrichments reflecting both lithological sources and sedimentary processes. Magnetic separation proved effective in enhancing the concentration of SRM‑bearing minerals, while SEM analyses provided crucial insights into mineral phases and potential ore associations.
These findings highlight the potential of fluvial sediments as secondary sources of SRMs and demonstrate the value of integrating magnetic separation, SEM mineral characterization, and geochemical proxies in regional exploration frameworks. Finally, this approach provides an effective preliminary exploration tool to delineate sediment provenance domains and identify high‑potential exploration targets at the basin scale.
[1] Kiss G., Molnàr K., Skoda P., Kapui Z., Garuti G., Zaccarini F., Palcsu L. and Czuppon G. 2023. Tracing the Source of Hydrothermal Fluid in Ophiolite-Related Volcanogenic Massive Sulfide Deposits: A Case Study from the Italian Northern Apennines. Minerals, 13 (1).
How to cite: Rotta, D., Bianchini, G., and Bonadiman, C.: Prospecting for Strategic Raw Materials in stream sediments through geochemical and mineralogical analyses: Case studies from Northern Italy, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-21661, 2026.
Processing of carbonatic rocks by lime industry produces scraps, some of which are not yet valorised. An example are the washing muds, separated between extraction of the carbonate material and its processing in the kiln. The subject of this study is the characterisation of trace elements in the washing muds from different quarries, related to various geological settings and different processing, with particular focus on critical raw materials (CRM), and their potential relation with major elements, geological features and age of the exploited rocks. The project, run in collaboration with Unicalce, the major Italian producer of lime, and Carmeuse, one of the primary producers in Europe and partner of Unicalce, led to the collection of samples from six quarries in Italy and two in Belgium.
Microfacies differences between quarries were determined through petrographic analysis on thin sections of the extracted rocks. The variability observed at microscale in the samples from a single quarry is partially lost due to the bulk blending during crushing and milling operated to prepare the load for the kiln. As a consequence, the muds resulting from washing of the milled rock, represent a blend of the lithologies extracted in a relatively short lapse of time and sent to the comminution plant.
Both rock and mud samples were collected for each site and processed into powder pellets for LA-ICP-MS analysis. Major and trace elements were measured, normalised and plotted accordingly. Rare earth elements were normalised to Post Archean Australian Shales (McLennan, 1989) and correlated with Ca, Mg and Al. Other traces were normalised to mean Upper Continental Crust (Rudnick & Gao, 2003), and concentration factors from rock to muds were calculated and plotted. Antimony is enriched in all studied muds, while Li, Cd, Sn and U have notable concentrations, considering the type of rock, with a wide variability range among the quarries. These concentrations are still only traces of few ppm, but the difference in trace element distribution between source rock and muds could serve as an important point of consideration in the future use of these materials and their potential recycling, since they constitute great volumes of unused material all throughout Europe.
McLennan S.M. (1989) Rare earth elements in sedimentary rocks: influence of provenance and sedimentary processes. Reviews in Mineralogy and Geochemistry, 21, 169-200
Rudnick R. L., Gao S. (2003) Composition of the continental crust. Treatise on Geochemistry, Volume 3, pp.659. ISBN 0-08-043751-6 Elsevier
How to cite: Piepoli, L. and Grieco, G.: Trace elements distribution and enrichments in lime industry washing muds, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7141, https://doi.org/10.5194/egusphere-egu26-7141, 2026.
Legacy flotation tailings from historical mining operations increasingly attract attention as secondary resources for strategic raw materials while simultaneously posing significant environmental risks. The former Sb–As–Cr mine of Lojane in North Macedonia represents one of the largest arsenic(As)- and antimony(Sb)-rich mine waste sites in the region, originating from the processing of hydrothermal vein-type mineralization hosted within the ophiolitic units of the Vadar Zone (Đorđević et al. 2019). Despite the extensive environmental concerns, the potential of these tailings as a resource has remained largely unexplored.
This study aims to assess the feasibility of sustainable recovery of Sb from the Lojane flotation tailings through a detailed mineralogical and geochemical characterization. This will be achieved by using powder X-ray diffraction (PXRD), inductively coupled plasma-optical emission and -mass spectrometry (ICP-OES/MS), and scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS), alongside evaluating environmentally relevant processes controlling metal(loid) mobility.
Bulk mineralogical analyses reveal a complex assemblage of primary and secondary Sb- and As-bearing phases, including realgar (AsS), pararealgar (AsS), arsenolite (As2O3), senarmontite (Sb2O3) and cervantite (Sb2O4) accompanied by abundant gangue minerals such as quartz (SiO2) and gypsum (CaSO4·2 H2O). This mineralogical diversity reflects the advanced oxidation and weathering processes that have affected the tailings as wells as indicating multiple mineralogical hosts for Sb and As.
Detailed chemical analyses reveal very high concentrations of As (124–480 g/kg) and Sb (12–87 g/kg), and elevated concentration of Fe (7–30 g/kg) as well as traces of Cr (20–190 mg/kg), Ni (90-2.560 mg/kg), Tl (50-205 mg/kg) and Co (10-130 mg/kg).
Electron microscopy investigations provide detailed insights into the micro-scale distribution of Sb- and As-bearing phases as well as their textural relationships with alteration products. The primary As–Sb sulphide assemblage, including relict realgar and stibnite, is pervasively overprinted by chemically heterogeneous cemented crusts containing shrinkage microcracks that form continuous intergranular matrices.
SEM-EDS reveals the presence of two groups of secondary matrices that commonly occur as pore-filling and grain-coating phases. The first group from the Fe-As-Sb-S-O system consists mostly of oxides (arsenolite, stibioclaudetite, hydroxy iron oxides, roméite group As-bearing Sb-oxides), arsenates (scorodite) and sulphates (gypsum). The second group, which is Si–Al–O dominated, consists predominantly of amorphous to poorly crystalline Si–Al oxides with systematically detectable minor contents of As, Sb, Fe and S.
Together, these observations indicate progressive supergene oxidation, element redistribution and the partial immobilisation of As and Sb within secondary phases. This exerts a key control on their environmental mobility and long-term stability.
By linking mineralogical controls, bulk chemistry and leaching behaviour this study provides a comprehensive framework for evaluating both the environmental risks and resource potential of complex As-Sb flotation tailings.
Tamara Đorđević acknowledges the financial support of the Austrian Science Fund (FWF) [Grant: P 36828-N].
Đorđević, T. et al. (2019): Can. Mineral., 57, 1–21.
How to cite: Vacek, K., Đorđević, T., Tasev, G., and Serafimovski, T.: Environmental risk assessment and antimony recovery potential from flotation tailings of the former Sb-As-Cr mine in Lojane, North Macedonia, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11875, https://doi.org/10.5194/egusphere-egu26-11875, 2026.
Extractive waste (EW) represents a significant environmental concern but also a strategic resource opportunity within the framework of the circular economy. This study focuses on the former Crocette and Pestarena gold mines in the Western Alps (NW Italy), which have left behind a significant environmental legacy. The study area is an alpine valley where paragneiss, micaschists and orthogneiss outcrop. At the valley floor, the metamorphic bedrock is covered by alluvial deposits hosting a phreatic aquifer that is hydraulically connected to surface waters.
The research focuses on EW deposits characterisation to assess both their potential for Critical Raw Materials (CRMs) recovery and the level of contamination and potential ecological risk affecting soils and sediments in the mining area.
The study integrates a significant collection of previously unpublished data, mainly focusing on EW and soils, with a 2024 sampling campaign to improve the understanding of EW deposit extension and to investigate their physical, geochemical and mineralogical characteristics.
Results reveal a matrix dominated by quartz, feldspars, and micas, along with secondary minerals (e.g. scorodite and jarosite) indicative of alteration processes. Residual pyrite and arsenopyrite, together with traces of scheelite and Ce-monazite, highlight the presence of associated CRMs. Geochemically, a significant enrichment of CRMs is detected, primarily driven by As, and secondarily by W, Sb, and Bi, with minor enrichment of Light Rare Earth elements (LREEs).
The environmental impact assessment identifies As as the main pollutant, classifying surrounding soils as heavily to extremely contaminated; Pb contamination is moderate. Overall, the potential ecological risk remains moderate. River sediments are uncontaminated; however, sediments from mine drainage tunnels and EW drainage channels also show contamination and potential ecological risk, confirming that environmental impacts are still ongoing more than six decades after mine closure.
The findings suggest that As, which represents the primary source of contamination at the site, is also the element with the greatest recovery potential. The recovery of As would not only ensure an additional supply of CRMs but could also, potentially, contribute to the mitigation of contamination at the site itself. This feasibility is further enhanced when As recovery is considered in conjunction with associated CRMs (Bi, Sb, and W). The estimated volumes of EW and their residual CRMs content indicate a significant potential for concurrent recovery. Overall, these results point toward a more sustainable mitigation strategy, by which part of the remediation costs could be offset by revenues derived from the recovery and commercialization of As and other CRMs, thereby coupling environmental risk mitigation with the valorisation of strategic resources.
How to cite: Zaniboni, L., Cavallo, A., De Luca, D. A., Lasagna, M., Padoan, E., Martin, M., and Dino, G. A.: From extractive waste to valuable resources: potential critical raw material recovery and contemporary environmental mitigation in the gold mines of the Western Alps (NW Italy), EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11612, https://doi.org/10.5194/egusphere-egu26-11612, 2026.
This study explores the potential recovery of critical raw materials (CRMs) from extractive waste generated during the exploitation of ornamental granite in the Montorfano and Baveno plutons (Verbania, Piedmont, Italy). Current industrial flowsheets are primarily designed to maximise the purity of quartz and feldspar concentrates for ceramic and glass applications. Consequently, separation strategies favour the rejection of middlings, consisting of quartz-feldspar particles partially intergrown with Fe-bearing minerals that would compromise final product specifications, but show enrichments in CRMs. These middlings still contain significant amounts of recoverable non-magnetic silicate minerals and could be valorised through targeted process optimisation. Granite offcuts are reprocessed to extract non-magnetic fractions rich in feldspar and quartz, classified by grain size and chemical purity, while the magnetic fraction - dominated by micas - is typically sold as construction filler. However, this magnetic by-product hosts REE-bearing accessory phases and moderate concentrations of strategic elements - REE, Y, Sc, Li, Ti, Mg, and Mn - representing an underexploited CRM source. Feldspar itself is classified as a CRM under the EU Critical Raw Materials Act (CRMA), further reinforcing the strategic relevance of improving recovery efficiency from granite waste streams. Moreover, the mica-bearing magnetic fraction offers opportunities for market diversification: mica can be further valorised for high-value applications, including cosmetic formulations that exploit its lamellar structure and optical properties. The research addresses mineralogical and processing constraints limiting selective recovery, including low-grade and heterogeneous assemblages, complex mineral intergrowths, and incomplete liberation. A key challenge lies in balancing comminution to achieve sufficient liberation prior to magnetic separation while minimising the generation of ultrafine particles, which - despite facilitating physical separation - negatively affect downstream processing. Additional complexity arises from overlapping magnetic susceptibilities between target phases and Fe-bearing gangue silicates, frequently resulting in mixed products with suboptimal enrichment. Beyond REE minerals such as monazite, allanite, and xenotime - commonly locked within biotite - several elements of interest are plausibly incorporated within the crystal lattice of micas, underscoring the importance of prioritising mica concentration as a pre-treatment step, followed by targeted chemical extraction routes. Process optimisation through refined magnetic separation could simultaneously increase the recovery of non-magnetic material for further processing and alternative quartz and feldspar applications, and improve the grade of the magnetic concentrate, enabling more efficient CRMs recovery. Although CRM concentrations remain modest compared to primary deposits, valorising these materials offers significant advantages, including reduced waste volumes, alignment with EU CRMA objectives, and leveraging existing infrastructure to minimise costs and permitting requirements. From a circular economy perspective, this approach supports near-zero-waste operations while mitigating the environmental impacts associated with primary mining. The study focused on comprehensive mineralogical and geochemical characterisation of feed granites and magnetic separation products using ICP-MS, XRF, XRPD, and SEM-EDS, combined with laboratory-scale processing trials. Both dry permanent magnet and electromagnetic separation techniques were evaluated across different granulometric classes to identify optimal operational parameters. The ultimate goal was to define a scalable processing protocol suitable for pilot-scale validation and integration into the current industrial flowsheet.
How to cite: Menso, I., Gioiello, S., Cazzaniga, A., and Storni, N.: From granite waste to strategic value: unlocking critical raw materials through magnetic separation process innovation, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7460, https://doi.org/10.5194/egusphere-egu26-7460, 2026.
Historic mines at Håkansboda located in western part of the Bergslagen mining district in west-central Sweden were selected as one of the pilot studies within the FUTURAM, a HORIZON EUROPE Research and Innovation project (2022-2026). FUTURAM’s main objectives is to map the supply of Critical Raw Materials (CRM) obtained from recycling of six waste streams: batteries, electrical and electronic equipment, vehicles, mining waste, slag and ash, and construction and demolition waste, and to develop a standard methodology for resource assessment, reporting structure, and guidance to improve the raw materials knowledge base up to 2050. Apart from building a database with Secondary Raw Materials (SRM) in Europe, several case studies were carried out to test different methods and approaches in order to evaluate the mineral potential and economic value of historic and current mining waste volumes. Additionally, UNFC was applied to SRM projects to test, develop, validate and demonstrate the procedures in line with UNFC requirements to enable fact-based decision making for their future exploitation.
In the Håkansboda historic mines, Cu and Co ore was mined since the XV century. Håkansboda deposit is located in the Guldsmedshytte syncline, folded during the Svecofennian orogeny with the stratigraphic sequence of metasedimentary and felsic metavolcanic rocks typical of central Bergslagen mining province. The Håkansboda polymetallic Cu-Co+Ag sulphide deposit is a SVALS-type, a stratabound Cu-Co (Fe, Sb, As, Bi, Ag and Au) mineralisation hosted in the so-called Håkansboda marble. The Håkansboda mineralisation occurs as disseminated sulphides of varying abundance in the marble horizon. It contains massive chalcopyrite-pyrrhotite rich ore bodies with surrounding less massive mineralization zones with various textures and composition. The main mineralogy is represented by chalcopyrite, pyrrhotite with subordinate arsenopyrite, pyrite, tetrahedrite-tennantite, sphalerite, molybdenite, cobaltite and Fe-Co sulphides. Native bismuth and gold can also be found.
Several groups of methods have been tested at Håkansboda: sampling routines, geochemical and mineralogical methods, and waste beneficiation methods. Geochemical methods including geochemical maps gave an overview of the chemical composition of the waste rocks with special emphasis on metals and critical raw materials and their spatial distribution in waste heaps. Mineralogical methods were used to identify the metal-bearing minerals and their parageneses/associations. The preliminary beneficiation tests helped to predict best possible extraction and processing technologies and validate the potential of waste for further extraction, including economic-related factors, such as the grade which can be obtained. At last, UNFC classification was developed upon the basis of quality of the parameters/controlling factors as well as their uncertainties supporting the level of confidence.
How to cite: Ladenberger, A., Arvidsson, R., Sädbom, S., Nysten, C., Korhonen, T., Buczko, D., and Casey, P.: Geochemical and mineralogical investigations of waste rock from the historic mines at Håkansboda in Bergslagen, Sweden, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-13854, 2026.
The element nickel is included on the critical raw materials (CRM) list as strategic raw materials, in line with the EU Critical Raw Materials Act. It is used for making stainless steel (about two-thirds of production), and in high-performance superalloys for demanding environments like jet engines. It's also critical for electric vehicle (EV) batteries, improving energy density, and for electroplating, magnets, coins, and chemical catalysts. Nickel is mainly extracted from sulphides ores (e.g. pyrrhotite and pentlandite) or from the silicate garnierite (lateritic ore), but in recent times, the mineral awaruite, a native nickel–iron alloy Ni2-3Fe, has gained considerable attention. Awaruite has unique characteristics compared to other nickel minerals: it does not contain sulfur, it has higher magnetic susceptibility than magnetite, and magnetic and gravity separation are feasible methods of awaruite concentration. The presence of this Ni-Fe alloy has been reported in ultramafic rocks (e.g. serpentinites) that underwent specific P-T-X conditions in prograde metamorphism, in strongly reducing conditions. For example, awaruite is an accessory mineral of the Valmalenco serpentinite (central Alps, northern Italy), a stone material used as dimension stone and for roof slabs, with different textures (massive and schistose) and color shades. The extraction and processing of serpentinite generate huge volumes of waste in the form of shapeless blocks, fragments and cutting sludge, with percentages ranging from 35 to 50 per cent of the initial volume. The waste materials were characterized from a chemical, mineralogical and petrographic point of view using ICP-OES, ICP-MS, XRPD, SEM-EDS and WDS, to assess their characteristics and potential reuse in various sectors. The whole-rock Ni content is high, ranging from 1400 to 2400 ppm, and Ni is present in trace amounts in silicates (e.g. olivine, serpentine), in the form of sulphides (pyrrhotite, pentlandite) and awaruite, in grains of approximately 10-30 µm. This Fe-Ni alloy is widespread in all commercial varieties of serpentine and represents the main Ni phase in these rocks. Among the various waste materials, the most promising is processing sludge, which has a fine grain size (less than 50 µm). In this type of waste material, the awaruite grains are already completely freed from the silicate matrix and can therefore be easily separated using magnetic and gravimetric techniques, without further grinding. The actual potential for recovering Ni from mining waste will be assessed through separation tests, combining this with the recovery of other minerals of industrial interest (e.g. olivine, serpentine) to optimize the recovery process.
How to cite: Cavallo, A.: Nickel recovery from serpentinitic waste materials: the potential of awaruite, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7211, https://doi.org/10.5194/egusphere-egu26-7211, 2026.
Historical and legacy mining waste deposits, such as tailings storage facilities and waste rocks, represent both a potential source of unrecovered critical and non-critical metals as well as a significant environmental challenge in Europe. The EU 2006 Extractive Waste Directive marked the first mandatory step for Member States to monitor mining waste, adopting a risk-based approach following environmental disasters in the 1990s.
In the 2010s, EU-funded projects like ProMine and ProSUM began mapping these deposits and developing a first pan-European database. National, federal and regional initiatives contributed to the multi-actor data collection and dissemination process. More recently, the EU-funded GeoERA programme and particularly the FRAME and MINTELL4EU projects further designed and established the MIN4EU database. This is now the reference pan-European resource, compiling information on mineral deposits and anthropogenic resources, including mining waste. However, until recently, updated datasets were not publicly accessible in a centralised and user-friendly format.
The FutuRaM project (Future Availability of Secondary Raw Materials – futuram.eu), in collaboration with GSEU (Geological Service for Europe – geologicalservice.eu) which associates thirty-seven geological surveys in Europe, aims to map and share data on the potential of critical raw materials in historical mining waste across the continent. Both projects have accelerated the collection and cataloguing of mining waste data. This effort is aligned with the Critical Raw Materials Act (Article 27), which requires EU Member States to establish a database of closed and abandoned extractive waste facilities, excluding sites where recoverable quantities of critical raw materials are unlikely. The database includes: (1) Location, area, and waste volume; (2) Operator information; (3) Quantities and concentrations of raw materials; (4) Additional relevant data for recovery.
The mining waste section of the MIN4EU database is now publicly accessible via the EGDI (European Geological Data Infrastructure – www.europe-geology.eu/) portal and the Urban Mine Platform (www.urbanmineplatform.eu/) developed within FutuRaM. Currently, it covers mining waste data from 20+ European countries. Gaps may exist due to limited historical mining activity or incomplete inventories, but the database remains dynamic, linked to national geological surveys and mining authorities. It is open to new contributions to better appraise the potential source of unrecovered critical and non-critical metals. The communication will present the structure of this database and showcase data access via the Urban Mine Platform.
FutuRaM is funded by the European Union (GA 101058522).
How to cite: Urvois, M., Monfort Climent, D., Bodénan, F., Albert, C., Arvidsson, R., Kumelj, Š., Bavec, Š., Hribernik, K., Žibret, G., Wittenberg, A., Meima, J., Karlsson, T., and Eloranta, T.: Urban Mine Platform and European historical mining waste database aligned with Critical Raw Materials objectives, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-9857, https://doi.org/10.5194/egusphere-egu26-9857, 2026.
Quartz and feldspar are critical minerals for industries such as glass, ceramics, and photovoltaic cell production. The European Union classifies feldspar as a Critical Raw Material (CRM), while quartz is the main precursor for silicon metal production, also listed as a CRM. Conventionally, their separation relies on flotation with hydrofluoric acid (HF) under strongly acidic conditions (pH 2-3) to enhance the electronegativity and hydrophobicity of feldspar towards the quartz recovery. However, the use of HF poses severe environmental and safety risks and increases operational costs due to its high corrosivity, toxicity, and environmental restrictions posed by EU member states’ legislations. This study aims to improve the efficiency and sustainability of acid flotation for the separation of quartz and feldspar from Minerali Industriali’s extractive waste streams by minimizing or potentially eliminating HF consumption. This is pursued through the fine-tuning of key flotation parameters and the introduction of alternative reagents, such as sodium fluoride (NaF), sulphuric acid (H2SO4), organic acids and innovative chemical compounds, while preserving selectivity and high separation efficiency. In parallel, a sustainable wastewater treatment strategy is being developed to further reduce the environmental footprint of the process, including water recirculation, neutralization, and purification. A preliminary laboratory-scale protocol is currently under development and involves multiple conditioning and flotation stages using water, HF, and cationic collectors (e.g., CustAmine® by Arkema) to recover a high-purity feldspar concentrate from a pre-treated feldspathic sand in the 100-600 µm grain size range. The experimental study is being supported by a Design of Experiments (DoE) integrated with chemical and mineralogical characterization of the feed material and flotation products – both concentrates and tailings - to enable systematic process optimization. Semi-industrial testing through a pilot plant will validate the proposed solutions under real operating conditions. Environmental and economic aspects will be evaluated by Life Cycle Assessment (LCA) and Cost-Benefit Analysis (CBA), comparing conventional and innovative processing routes. Overall, this approach promotes circular economy strategies through by-product reuse, and contributes to safer and more sustainable mineral processing practices supporting the transition towards environmentally responsible industrial operations, while providing deeper insights into the flotation behaviour of quartz and feldspar under both conventional and innovative reagent schemes. The project is partially funded by the Italian Ministry of the Environment MASE (Ministero dell’Ambiente e della Sicurezza Energetica), and involves Minerali Industriali – R&D&I+QCLab Department - as the industrial partner and three different departments of the Università degli Studi di Torino – namely Department of Chemistry, Department of Earth Sciences, and Department of Management "Valter Cantino".
How to cite: Gioiello, S., Menso, I., Baglietto, C., Cazzaniga, A., Storni, N., Dino, G. A., Mancini, S., Malandrino, M., Bertinetti, S., Vesce, E., and Lippi, G.: Optimization of acid flotation for quartz-feldspar separation from extractive waste, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-16715, 2026.
The climate emergency impacts settlements, infrastructures and ecosystems both through permanent flooding of the lowest‐lying areas and by increasing the frequency and/or severity of storm surges over a much larger region. In response to these challenges, the urgency in green renewable energies transition and vehicle electrifications to reduce the greenhouse gases emissions aligns with the growing need for enhanced electrical storage capacity, predominantly reliant on Li-based batteries. Notably, Li extraction is predominantly sourced from brine pumping and evaporation in salt flats, arid environments necessitating a shift toward Zero-Water consumption in extraction procedures. With this objective, mining companies have proposed a new extraction methodology based on Li recovery without evaporation and later brine reinjection in the aquifer, reducing at the same time cost and environmental impact, aligning with Horizon Europe cluster 5 of agenda 2030. Our research aims to develop a novel hydrogeochemical framework that helps to understand the effect of brine reinjection in salt flat, combining 3 fundamental research plans: 1) the hydrogeological characterization in salt flat focused to fiend the most favorable areas for brine injections, as well as monitoring the evolution of hydrological parameters at the aquifer during injection test for later implementation in 3D models. 2) the hydromechanical analysis of surface deformation associated with brines injection, looking to calculate the storage capacity and identify hydrogeological discontinuities. 3) the geochemical framework around brine mixing and brine-rock interactions affronted by modeling, lab and field samples characterization for later implementation in reactive transport models. A reinjection test carried out at a salt flat has studied by analyzing the generated hydrogeological and geochemical data, combined with historical deformation data. Descents in phreatic level influenced by injection has been characterized and included in a transport model. Geochemical reactions, including brine mixing and brine-rock interactions has ben also characterized by reactive transport models calibrated with field data. Elucidating the whole set of geochemical processes that affect salt flats, as well as their combination with hydrogeologic and interferometric analysis will help to adapt predicting 3D models to new extraction strategies.
How to cite: Carrero, S., Concha-Dimas, A., Crisóstomo, B., Jurado, D., Vazquez-Suñé, E., and Valdivielso, S.: Implementation of hydrogeological and geochemical models in new strategies for Li extraction in salt flat, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19892, 2026.
The rapidly growing demand of lithium for batteries, mainly driven by the expansion of electric transportation and large energy storage systems, has increased the need for efficient and environmentally sustainable extraction methods. As Europe works to strengthen its strategic independence regarding critical raw materials, developing sustainable lithium production approaches has become a top priority.
Beyond the successful implementation of the selected technology, the environmental impacts of different extraction routes are of equal importance and must be carefully considered. However, assessing these impacts remains complex, as they are strongly influenced by both process design parameters and the natural characteristics of the lithium-bearing raw material. Traditional direct extraction methods, despite their broad use, require substantial time, water, energy, and chemicals, raising concerns about their overall ecological footprint. In response to this bottleneck, a range of innovative technologies, including nanofiltration, solvent extraction, electrodialysis, and adsorption, have been developed to improve the efficiency on the use of natural resources and to reduce environmental impacts. Despite significant technological progress, detailed and comparable assessments of the environmental impacts of lithium extraction technologies within the European context remain limited. This study seeks to help address this gap by conducting a comprehensive Life Cycle Assessment (LCA) of different lithium extraction routes. Utilizing various inventories to analyze the extraction of lithium with various technologies, LCA utilized the Environmental Footprint 3.1 methodology, the Eco-invent database 3.8, and SimaPro software. The goal is to estimate different environmental impacts of 1 kg lithium carbonate production within the European region.
The study examines not only the innovative technologies introduced to the mining sector, but also compares them with the well-establish benchmark, the conventional direct extraction, methods traditionally employed to extract lithium carbonate.
The comparison of new technologies shows that nanofiltration has the lowest environmental impact, whereas solvent extraction remains the most impactful. When comparing various new technologies with the conventional method, solvent extraction consistently demonstrates the highest environmental impact across most categories. Adsorption also plays a key role in environmental impacts, escalating resource use and climate change.
Overall innovative lithium extraction technologies exhibit varying levels and types of environmental impact. Since solvent extraction remains the most efficient method for extracting the desired purity of lithium from the source adopting bioleaching and renewable energy resources can mitigate the corresponding impacts . It has been observed that selecting the appropriate extraction method depends heavily on the source of the raw material resource. Consequently, the adoption of the most efficient and suitable technology should be tailored accordingly.
How to cite: Baradaran Kazemian, P., Alexious, V., Galanos, C., Yakoumi, I., and Baricco, M.: The environmental impacts of the lithium extraction in the European region: a comparative study of conventional and new technologies to produce lithium carbonate, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7302, https://doi.org/10.5194/egusphere-egu26-7302, 2026.
Global lithium demand is increasing rapidly, with approximately 87% of projected growth driven by Lithium-ion batteries and the expansion of electric vehicles. This trend raises critical questions regarding the availability of lithium resources, the diversity of supply sources, and the economic viability of extraction. This study presents a comprehensive comparative assessment of the main lithium deposit types, including salar brines, granitic pegmatites, and sedimentary deposits. These deposits are classified according to their geological characteristics, typical size and grade ranges, geographic distribution, and global resource and reserve estimates. Beyond the resource base, the study examines the technical and economic aspects of lithium production for each deposit type. The global lithium value chain is mapped, and the principal processing routes leading to lithium carbonate equivalent (LCE) are analyzed. A techno-economic modeling framework is employed to estimate capital expenditure (CAPEX), operating expenditure (OPEX), project development timelines, and life cycle assessment (LCA) indicators, enabling consistent comparison across production pathways. Based on this framework, the contribution of different deposit types and grade classes to future global lithium supply under alternative market and policy scenarios will be assessed. A competitive classification framework will be developed to identify the deposits most likely to enter production, considering technical feasibility, economic competitiveness, and environmental constraints.
How to cite: Mortada, Z.: Techno-Economic Assessment and Supply Forecasting of Lithium from Primary Sources, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-6490, https://doi.org/10.5194/egusphere-egu26-6490, 2026.
Lithium is central to energy transition as the key element of electric vehicles and grid storage, but its expanding is accompanying with worsen environmental pressures. Existing studies fall short in exploring the full mitigation potential of environmental impacts due to the reliance on a descriptive approach of comparing predefined options. Here we develop an artificial intelligence-driven life cycle assessment methodology to assess 18-dimensional environmental performance for global 121 mining sites, and further optimize global lithium supply portfolios from 2025 to 2050 across four demand scenarios. The optimization model enforces real-world constraints for project commissioning, capacity ramp-up and resource depletion to enable actionable insights. Results indicated that optimized portfolios lower cumulative burdens across 18 environmental dimensions by 53.3–61.8% on average compared to the baseline scenario, with the most reliable gains for climate and health impacts. While water use falls only modestly, and mineral resource scarcity can worsen as other impacts decline. Optimized portfolios suggest a brine-based supply by Chile’s Atacama and Argentina’s Cauchari-Olaroz, Olaroz, and Tres Quebradas, followed around 2035 by accelerated Australian spodumene (Pilgangoora, Mt Holland, Greenbushes) and diversification from other countries. The results point to practical levers for industry and policy stakeholders to prioritize supply sources to align surging lithium demand with multi-dimensional environmental goals.
How to cite: Sun, X.: A prescriptive optimization framework for designing sustainable lithium supply portfolio, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-2174, https://doi.org/10.5194/egusphere-egu26-2174, 2026.
How to cite: Maus, V.: MINE-THE-GAP: Satellite Earth Observation and AI to Map Global Mining Footprints and Support CRM Transparency, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-21341, 2026.
Global demand for the critical raw material copper is projected to increase by approximately 75% by 2050, driven by the growing uptake of advanced technologies and rising material demand for housing and energy infrastructure, particularly in low- and middle-income. While copper recycling is expected to increase, with recycled materials expected to supply about half of total demand by 2050, this rising demand will also require significant expansions in copper mining.
One crucial challenge for the expansion of copper mining is its water use, which is critical at different stages in metal mining and processing. Differences in the processes in place at each site are, therefore, important determinants of water demand and water intensities, which can vary considerably among extraction sites.
Depending on the geographical location of the mine, availability and sources of water as well as the impacts related to their use can vary considerably. As metal mining is often taking place in vulnerable hydrological settings, water use can have considerable impacts on local water scarcity and water quality, leading to or aggravating competition for local water resources which often result in open conflicts. It is hence essential that assessments of mining impacts on water resources consider the local environmental and socio-economic contexts. However, comprehensive assessments of water use in copper mining are limited due to the lack of consistent datasets tracking the actual demand at individual mines worldwide.
This work presents a comprehensive spatially explicit analysis of water use in copper mining, taking into consideration multiple determinants of water input at mine site level. We employ machine learning (ML) to estimate mine-specific water use, which we then integrate with satellite-derived trends in freshwater availability and local water scarcity indicators at each mining site to assess the pressure on water resources. The ML models are trained on available water use data compiled from multiple sources with a predictors space including a wide set of variables: production quantity, primary or by-product classification, mine type, geological setting, process route, ore grade, and potential evapotranspiration. Since data on water is not often reported, the ML models enable to comprehensively estimate global water use across all known copper-producing mines.
The analysis reveals spatial and temporal variations in water use across global copper production in relation to local characteristics such as process types in place, geological setting, and water availability. Results show that global water intensity is two-fold higher than previously known. Between 2015 and 2019 copper mines withdrew 13.6 trillion litres of water, with water use increasing at a rate 50% higher than copper production. In 2019, more than half of global copper output came from sites with decreasing freshwater availability and rising water demand, with notable contribution from Latin America, the largest copper producer and water user.
Our analysis is relevant to public and corporate policy, revealing concerning spatial patterns on water use that can threaten future mine production, cause local conflicts and ultimately put global sustainability strategies at risk.
How to cite: Lutter, S., Wegner Maus, V., Luckeneder, S., and Tost, M.: Increasing Water Use in Global Copper Production Threatens Freshwater Availability, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-21219, 2026.
Despite water playing a critical role in nearly every stage of mining activities, substantial uncertainty remains about the extent to which mine operations pollute downstream water bodies. In this study, we develop and parameterize a transferable model to estimate the grey water footprint (GWF) of mine sites. The GWF represents the volume of water required to dilute mine-derived pollutants to safe levels in receiving waters, accounting for both pollutant release rates and natural background concentrations. Applying the GWF concept to systematically evaluate the water quality impact of large scale mine operations is challenging due to the diversity of pollutants and emission pathways, and because relevant data is scarce, uncertain, and dispersed across numerous text sources. We address this challenge by combining natural language processing and probabilistic estimation. NLP is used to infer from publicly available documents plausible concentration ranges and treatment or immobilization efficiencies across processing steps. We then reduce parameter dimensionality and propagate uncertainties through sensitivity analysis and Monte Carlo simulations. We demonstrate the model’s practical utility by applying it to a representative copper mining site. The strength of our approach lies in its versatility: it adapts to available data at the site level while producing outputs that are readily comparable across sites and linkable to mine typologies, supporting more effective water and pollutant management strategies.
How to cite: Faure, J., Muller, M., D'Odorico, P., and Kunz, N.: Using Natural Language Processing to estimate the grey water footprint of mines, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19743, 2026.
The supply security of Critical Raw Materials (CRMs) has led to the adoption of the European Union Critical Raw Materials Act (CRMA), drawing increased attention to the occurrence of CRMs in both primary deposits and secondary sources, including extractive waste. The CRMA explicitly refers to the United Nations Framework Classification for Resources (UNFC) as a reporting and classification system, and strategic projects are expected to apply UNFC principles. However, a key challenge for project developers lies in identifying and applying the technical, environmental, economic, social, and legal criteria required for consistent UNFC-based classification, particularly for anthropogenic and extractive waste resources.
Within the Horizon Europe project FutuRaM, a structured anthropogenic resource assessment tool, SARA4UNFC, was developed to address this challenge and to guide project developers through the UNFC classification process. SARA4UNFC is implemented as a web-based decision-support tool that operationalises the UNFC through a transparent, stepwise procedure covering project definition, recovery process selection, stakeholder identification, evaluation of controlling factors, and final resource classification, with emphasis on influencing environmental-socio-economic viability, technical feasibility, and the level of confidence in the estimated quantities of the products.
The assessment framework integrates two complementary methodological layers. At the early screening stage, a five-step UNFC-compliant screening procedure is applied to support rapid, data-efficient identification of project potential and key barriers using publicly available information and expert judgement. This screening phase enables an initial classification of projects and supports decisions on whether further detailed evaluation is warranted. Projects that pass screening proceed to a structured seven-stage assessment procedure designed for prefeasibility and feasibility levels.
The seven-stage procedure incorporates project development phase–specific requirements. It supports the systematic selection and evaluation of controlling factors in accordance with the chosen context of evaluation in the Realm of Discourse (ROD), including law-based, circular economy–oriented, and sustainability-focused assessments. By systematically linking project-specific information to UNFC categories, SARA4UNFC facilitates traceable documentation of assumptions and results, including data sources, throughout the classification process, based on expert judgements. This approach enables the development of alternative recovery pathways and the identification of key project constraints and risks. The structured workflow improves transparency and comparability across projects while supporting alignment with regulatory and sustainability objectives. Through selected use cases related to extractive waste valorisation, the tool demonstrated its applicability for supporting responsible resource management. SARA4UNFC thus meets the policy-driven classification requirements stipulated in the Critical Raw Materials Act of the EU. In addition, structured data collection and the assessment of relevant factors enable fact-based decision-making at the project level.
Keywords: Resource recovery; Project classification; Secondary raw materials; UNFC; Web tool
How to cite: Heuss-Aßbichler, S., Jayasinghe, L. B., Dorri, I., and Jimenez Gomez Tagle, M.: SARA4UNFC: A holistic approach to assessing mining and extractive waste activities, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-22292, 2026.
Posters on site: Wed, 6 May, 08:30–10:15 | Hall X4
The increasing demand for critical raw materials (CRMs) utilized in green energy systems, batteries, and electronic devices has enhanced the exploration of unconventional ore systems, such as karst-type bauxites, which are host to economically significant Rare Earth Elements (REEs) and associated critical metals (e.g., Li, Ga, Zr, and Sc). Karst bauxite deposits have been documented in Paleocene strata of the northwestern Himalayan foreland basins, Pakistan. However, the resource potential and beneficiation restrictions have not been adequately assessed yet. The present study measures grade variability, host phases, distribution, and enrichment of REEs and associated CRMs to assess their economic values. Ten bauxite outcrop sections were studied in the northwestern Himalayan fold and thrust belt of Pakistan, including the Hazara–Kashmir Syntax (HKS; n = 2), the Attock–Cherat Ranges (ACR; n = 3), the Trans-Indus Ranges (TIR; n = 2), and the Salt Range (SR; n = 3). The bauxite horizons are overlain by the Paleocene Hangu Formation and underlain by Cretaceous units (HKS, ACR, TIR) and Cambrian to Permian strata (SR). An integrated workflow consisting of fieldwork, XRD, SEM-EDS, XRF, and ICP-MS was used for mineralogical and geochemical characterization. The geochemical data reveal that the ores are primarily bauxitic clays with low to moderate ΣREE concentrations that vary regionally. The average concentrations of ΣREE are 174 ppm (SR), 287 ppm (TIR), 344 ppm (ACR), and 66 ppm (HKS). Compared to the Upper Continental Crust (UCC), Al2O3, Fe2O3, and TiO2 are enriched, while SiO2 is depleted. The CRM-relevant trace elements (Ga, Zr, V, Hf, Nb, Ta, Th, and U) show positive anomalies, indicating widespread but generally low enrichment. The SEM-EDS results reveal that ultrastable accessory minerals, especially zircon, tourmaline, and rutile, are the common carriers of REEs in the studied bauxites. This implies that the ultrastable detrital phases host many REEs, which may have an impact on extractability. However, cerianite (CeO₂) is an additional important REE-bearing phase that is compatible with a positive Ce anomaly in the Salt Range. In the TIR, fluorapatite contributes to REE hosting (notably Ce, Nd, La, and Y); moreover, minor concentrations of REEs like Yb, La, Eu, and Ce also occur as trace, finely dispersed components within the matrix. The CRM distribution is mostly controlled by the strength of lateritization, which is normally weak to moderate but increases locally in Fe-rich horizons. Unlike other REEs, Ce was probably mobilized during intense ferrilitic weathering of primary REE minerals and then redistributed as cerianite (CeO₂), resulting in a positive Ce anomaly. From an economic perspective, the grade heterogeneity and the predominance of REEs in ultrastable minerals suggest that the prospectivity of CRM relies on identifying enriched layers and determining whether REEs are locked in resistant detrital hosts or occur in processable authigenic phases (cerianite, fluorapatite, monazite, or bastnäsite).
How to cite: Khubab, M., Wagreich, M., Iqbal, S., Schopfer, K., Ullah, M., and Ullah, S.: Critical Raw Materials in Paleocene Karst Bauxites of the Northwestern Himalayas, Pakistan: Grades, Host Minerals, and Economic Implications, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11493, https://doi.org/10.5194/egusphere-egu26-11493, 2026.
Karst bauxites are traditionally exploited as the principal source of aluminium, but recent studies have highlighted their growing importance as non-conventional resources for critical raw materials (CRMs), particularly rare earth elements and yttrium (REY), as well as gallium (Ga) and scandium (Sc). This contribution provides a comparative overview of the REY-hyper-enriched karst bauxites of the Sierra de Bahoruco, southwestern Dominican Republic, and Mediterranean karst bauxites, with emphasis on differences in geochemistry and mineralogy.
The REY-hyper-enriched bauxites of the Sierra de Bahoruco display highly variable REY contents, ranging from several hundred ppm to nearly 3 wt%, with median values two to three times higher than those of Mediterranean karst bauxites. In the Bahoruco samples with highest REY contents, the hosting mineralogy is dominated by discrete REY-bearing phosphates and/or carbonates, including monazite, xenotime, rhabdophane, churchite, and bastnäsite-group minerals. By contrast, in bauxites with moderate REY contents, Al-hydroxides, mostly gibbsite, represent the principal REY host, with REY occurring largely as adsorbed species. Mediterranean karst bauxites, mainly of Mesozoic age, typically exhibit only moderate to low REY contents, generally on the order of a few hundred ppm, and are hosted by Al-oxyhydroxides, predominantly boehmite.
Gallium and scandium are consistently present in both Mediterranean and Dominican Republic karst bauxites at levels of potential economic interest. Consequently, Ga and Sc are regarded as promising by-products of bauxite and alumina processing, regardless of geographic setting, whereas REY enrichment and mineralogical controls vary significantly between Mediterranean and Dominican karst bauxite systems.
How to cite: Tisora, À., Domínguez-Carretero, D., Villanova-de-Benavent, C., Torró, L., Bover-Arnal, T., Tavazzani, L., Llovet, X., Proenza, J. A., and Chelle-Michou, C.: Karst bauxites as a non-conventional source of Critical Raw Materials: insights from Mediterranean and Dominican Republic deposits, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-20373, 2026.
Starting from May 2024, the Critical Raw Materials Act entered into force in the European Union with the purpose of ensuring access to a secure, resilient, and sustainable supply of Critical Raw Materials (CRMs), including by enhancing efficiency and circularity throughout the entire value chain. Within this regulation, particular emphasis is devoted to the recovery of CRMs from extractive waste. Equal importance is given to the inventory of waste facilities, which must be carried out by Member States in order to obtain a clear framework in geographic, legal, volumetric, and compositional terms.
In Italy, the Sardinia Region is characterized by a remarkably high number of waste deposits originating from ornamental granite extraction. These materials have potential for the recovery of some CRMs such as Rare Earth Elements, due to the presence of allanite, as well as feldspars for the ceramic industry [1–2]. However, the decline of the ornamental granite sector in Italy has resulted in a lack of updated data, making it impossible to estimate either the total amount of granite waste or its potential as a source of CRMs. In this context, the present study aims to estimate the volumes and potential CRMs supply associated with granite waste deposits in the Buddusò–Alà dei Sardi extractive district (Sardinia, Italy).
Using QGIS software and available spatial datasets, extractive areas within the district were identified, and waste dumps were mapped based on satellite imagery. Given the absence of detailed Digital Elevation Models (DEMs) for the study area, these were reconstructed from satellite data, enabling the estimation of dump volumes. The resulting volumes showed a Root Mean Square Error (RMSE) of approximately 27% compared with more accurate DEMs. Subsequently, based on literature data concerning the composition of local granites and potential concentration processes for CRMs described by Aquilano et al. [1] and Vaccaro et al. [2], the potentially recoverable quantities of CRMs were calculated.
Although the results are characterized by relatively high uncertainty, this approach provides a preliminary dataset for extensive areas where significant data gaps currently exist and where achieving high-accuracy estimates in the short term appears unrealistic. Moreover, extending this framework to the entire Region of Sardinia could support the identification of the most promising areas for more detailed investigations, ultimately improving data quality and targeting zones with the highest potential for CRMs recovery.
[1] Aquilano, A.; Marrocchino, E.; Vaccaro, C. Gravity and Magnetic Separation for Concentrating Critical Raw Materials from Granite Quarry Waste: A Case Study from Buddusò (Sardinia, Italy). Resources 2025, 14, 24.
[2] Vaccaro, C.; Aquilano, A.; Marrocchino, E. Alternative Sources of Raw Materials for the Ceramic Industry through Granite Waste Recycling: A Case Study from Buddusò, Sardinia, Italy. Appl. Sci. 2024, 14, 7967.
How to cite: Aquilano, A., Marrocchino, E., and Vaccaro, C.: Estimating Volumes and CRM Recovery Potential from Granite Wastes in the Buddusò–Alà dei Sardi District (Sardinia, Italy), EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-18435, 2026.
The European Union has set a target of producing 10 % of its Critical Raw Materials (CRMs) demand by 2030, in order to reduce its dependency on imports (Critical Raw Materials Act, 2024). Achieving this short-term goal is only possible through an increased CRM supply from non-traditional sources, such as historic mine wastes (HMWs). As early mining prioritized high-grade ore and relied on less effective separation techniques, HMWs can still have elevated concentrations of critical and precious metals. Sulfide-rich waste is of particular interest, as it can contain a variety of elements that tend to associate with sulfide minerals (including Ag, As, Au, Cu, Co, Ni, Sb and Te) and can also cause environmental impacts, such as acid mine drainage or metal(loid) contamination of soil and water (Göbel, 2024; Hiller, 2024; Gopon et al., 2025).
To evaluate the residual CRM potential and the associated environmental impacts of HMWs, detailed sampling campaigns have been carried out in a former copper-gold mining district in the Upper Mur Valley (Styria, Austria). In this area, sulfide-rich ore was primarily mined during the 18th and 19th century, resulting in numerous small, generally overgrown waste rock piles. Whole rock geochemical analyses of the sampled waste rock show a strong heterogeneity of the CRMs present in the HMWs, indicating spatial differences in the mined ore. Elevated concentrations of copper, arsenic (both up to 0.6 wt.%), and gold (up to 2.4 g/t) highlight a remaining economic potential for the recovery of both critical and precious metals.
Additionally, a significant environmental impact was revealed by a monthly stream water sampling campaign in combination with metal(loid) analysis by inductively coupled plasma mass spectrometry (ICP-MS). In several streams at the study site, the concentration of arsenic surpasses the WHO drinking water guideline of 10 µg/l (WHO and UNICEF, 2018), with maximum concentrations reaching more than 500 µg/l. The identified sources for the release of arsenic are weathering HMWs and effluent water from open mine adits. Strong spatial heterogeneities of the arsenic concentration and speciation in the stream waters also indicate variations in the waste material and favourable conditions for the release of arsenic.
The results of waste rock and stream water analyses highlight the importance of an interdisciplinary approach on HMWs, which can be both of economic interest and environmental concern at the same time. The work at the study site in the Upper Mur Valley is part of the SCIMIN-CRM project, which is evaluating the CRM potential of mine wastes at four different locations across Europe and is funded by the European Union (Horizon Europe, No. 101177746).
References:
Göbel, E., 2024, Sulfide Geochemistry of the Hohen Tauern Historic Gold Districts (Austria). Montanuniversität Leoben.
Gopon, P., et al., 2025, Revealing Yukon’s hidden treasure (…). Mineralium Deposita, doi:10.1007/s00126-024-01325-9.
Hiller, J., 2024, A green future from a contentious past: Gold and critical metals in a historic arsenic mining district Straßegg (Styria). Montanuniversität Leoben.
WHO and UNICEF, 2018, Arsenic Primer: Guidance on the Investigation & Mitigation of Arsenic Contamination. ISBN: 978-92-806-4980-2.
How to cite: Dunkel, F., Bertrandsson Erlandsson, V., Wolf, L., Rittberger, M., Bandoniene, D., Wagner, S., Irrgeher, J., and Gopon, P.: Historic mine waste - A potential source for critical metals and environmental contamination? A case study from Styria, Austria, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7712, https://doi.org/10.5194/egusphere-egu26-7712, 2026.
South Korea depends largely on imports to secure its critical minerals. In the case of lithium, 66% of the demand is imported from China and 31% from Chile, while the price of Lithium continues to rise with the growth of the battery market. By the end of 2025, copper prices are expected to continue rising due to the supply crisis, intensifying the competition for securing resources. To address this international resource-securing crisis, this research focuses on the possibility of recovering metals from waste resources generated by domestic renewable energy facilities.
South Korea operates four Future Waste Resources Base Collection Centers to collect waste batteries from electric vehicles(EV), waste solar panel and wind turbine, conducting performance assessment and resale. However, a detailed analysis of whether waste batteries and panels are reused or recycled is not traceable, thereby limiting the accurate measurement of resource-circulation efficiency.
Although the recovery rates of waste batteries is high(about 14,000 units in 2024), but it is not traceable whether they are reused for energy storage systems(ESS) or recycled for resource recovery. To address this limitation, since 2025, the introduction of the Battery Lifecycle Management System has enabled full lifecycle tracing of EV batteries, whereas batteries from other sources remain outside the tracking system.
Since 2023, the implementation of the Extended Producer Responsibility system for waste solar panels has aimed to enhance resource-circulation efficiency. But the actual quantities recycled, reused, or simply discarded remain unclear, even if the projected amount of waste solar panels in 2025 is 14,596 tons according to the Korea Environment Institute.
While attention is often given to the recycling of wind turbine blades, wind power facilities also possess significant potential for metal resource recovery, as they contain approximately 4.3 tons of copper per MW in onshore installations and 9.6 tons per MW in offshore installations. In particular, a recovery potential of approximately 1,870 tons of copper is estimated from about 483MW of wind power facilities that are expected to reach the end of their life cycle in the early 2030s. Nevertheless, the recycling status of components other than nacelles and blades, such as towers and cables, remains entirely unverified.
Therefore, the introduction of a full-lifecycle tracing system for renewable energy waste resources is proposed. Similar to the Battery Lifecycle Management System, identification numbers are assigned to solar panels and wind power facilities so that the entire process from production to disposal and recycling can be traced, thereby visualizing the domestic circulation path of metal resources and providing a basis for enhancing the actual recycling rate.
How to cite: Kim, J. and Park, H.-D.: Lifecycle Traceability System for Metal Recovery from Renewable Energy Waste in South Korea, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-6063, https://doi.org/10.5194/egusphere-egu26-6063, 2026.
The transition toward clean energy systems and sustainable industrial development in Europe hinges on secure access to critical raw materials. In response, the project Development of the Mining Sector in Lapland, Northern Ostrobothnia, and Kainuu was launched in September 2024 to strengthen regional competencies, foster research and innovation, and enhance industrial engagement across Finland’s northern regions. Co-funded by the EU Just Transition Fund, the initiative aligns with Finland’s mineral strategy and the EU Critical Raw Materials Act, aiming to advance the mineral and battery value chain, support circular economy principles, and reinforce strategic autonomy.
The project seeks to promote regional collaboration through thematic workshops and joint events with industry development organizations, enhance international engagement by participating in EU-level dialogues and global mining forums, and support innovation and training through seminars, best practice dissemination, and the development of new project initiatives. Since its inception, the project has actively participated in and organized numerous events to build networks and share knowledge. Highlights in Finland include the Oulu Mining Summit in 2024 and 2025, which introduced the project and engaged stakeholders; FinnMateria and Kokkola Material Week in 2024 and 2025, which strengthened networking and collaboration with regional and national actors. Significant contributions include participation in the OECD Conference of Mining Regions and Cities in Rovaniemi, which highlighted regional initiatives in an international context and strengthened dialogue on mineral strategy challenges. Raw Materials Week in Brussels in 2024 and 2025 showcased Finnish expertise at the EU level. The project also fosters scientific exchange through its presentation at the EGU General Assembly in 2025, promoting collaboration across European raw material value chains. Additional activities include Swedish Mining Innovation Days, FEM 2025, the EU Arctic Forum, and targeted workshops with industry and policymakers.
Expected outcomes of the project include strengthened regional innovation ecosystems and improved stakeholder networks across Finland and Europe, policy recommendations that reflect the specific conditions of northern mining regions for integration into EU strategies, and the initiation of new collaborative research projects and training materials supporting the mineral and battery value chain. Furthermore, the project aims to increase the visibility of Finnish expertise in critical raw materials at European and global levels, contributing to a resilient and sustainable supply chain that underpins the green transition.
How to cite: Kupila, J., Panttila, H., and Pihlaja, J.: EU JTF-Project: Development of the Mining Sector in Eastern and Northern Finland - Results Achieved So Far, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-6638, https://doi.org/10.5194/egusphere-egu26-6638, 2026.
Critical Raw Materials (CRMs) are vital to modern technologies and key sectors such as renewable energy, electronics, and aerospace. Growing geopolitical, environmental, and market risks make supply diversification essential. Mining residuals, including tailings and waste rock, often retain significant CRM concentrations due to past processing inefficiencies, ore grade changes, and advances in extraction technologies. Exploring and recovering CRMs from these residual resources can contribute to resource security and support circular economy objectives.
This study evaluates an integrated multispectral infrared spectroscopy approach, combined with machine learning, to identify and map CRM-hosting mineral phases in mining residuals.
Reflectance spectra in the visible–near infrared (VNIR) and shortwave infrared (SWIR) ranges (0.35–2.5 µm) were acquired using an ASD FieldSpec instrument. Mid- to long-wave infrared spectra (2.5–15 µm) were collected using a Fourier Transform Infrared (FTIR) 4300 spectrometer. Together, these data provide complementary mineralogical information across a broad infrared spectral range. Spectral interpretation was conducted to identify the different mineral phases. The spectral datasets were analysed using supervised machine learning techniques, specifically support vector machines (SVM) and partial least squares – discriminant analysis (PLS-DA). These methods were used to classify materials into relatively high- and low-CRM concentration classes, supported by mineralogical and geochemical reference data.
Integrating VNIR–SWIR and FTIR spectral data enhances discrimination of CRM-hosting mineral assemblages and supports spatial mapping in heterogeneous mining residual deposits. When combined with machine learning, infrared spectroscopy offers an efficient tool for rapid assessment of secondary CRM resources. This scalable method can be applied to three-dimensional modelling to quantify CRM distributions within tailings volumes.
Overall, this integrated methodology enhances the mineralogical and geochemical characterization of mining residuals, supporting informed decisions for secondary resource exploration and recovery.
How to cite: Li, T., Desta, F., and Buxton, M.: Multispectral Infrared and Machine Learning Methods for Assessing Critical Raw Material Potential in Mining Residuals, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11566, https://doi.org/10.5194/egusphere-egu26-11566, 2026.
The growing demand for critical raw materials (CRMs), such as lithium, nickel, manganese, and cobalt, is increasing the importance of secondary resources derived from lithium-ion battery recycling. At the same time, improper management of end-of-life batteries may pose potential environmental risks. Understanding the processes controlling metal mobilization from battery-derived materials is therefore crucial, both for assessing their environmental impacts and for developing safe and responsible strategies for CRM recovery.
This study investigates metal mobilization from lithium-ion battery black mass under rhizospheric conditions, characterized by variable pH and the presence of organic compounds. Batch leaching experiments were conducted over seven days using two particle size fractions (<250 µm and >1 mm). The material was exposed to artificial root exudates and demineralized water, both at pH 3.5 and 6.7. Concentrations of Mg, Fe, Cu, Zn, Al, Mn, Ni, Co, and Li in leachates were determined using ICP-OES. In addition, SEM-EDS was applied to characterize particle morphology and elemental distribution before and after leaching.
The results demonstrate that acidic conditions combined with organic compounds significantly enhance metal mobilization, particularly for Al and Cu, which reached extraction levels of up to ~75% and ~55% respectively, while Ni, Mn, and Co exhibited lower but still measurable extraction efficiencies up to 4.33%, 5.52%, 4.08% respectively. In artificial root exudates at pH 3.5, the concentrations of several elements were one to several orders of magnitude higher than those obtained in demineralized water. Leaching factors (ARE/H2O) reached 32.5 for Cu and 22.5 for Al in the fine fraction, and increased to 4099 for Al and 2127 for Ni in the coarse fraction. Despite these higher factors in the coarse fraction, a clear particle-size effect was observed, with the fine fraction generally exhibiting higher relative extraction, while coarse particles occasionally released greater absolute metal amounts. In contrast, lithium displayed consistently high mobility across all tested media, pH levels and particle sizes, with comparable extraction of ~15-20%, and leaching factors ranging between ~1.0 and 1.6.
These findings demonstrate that rhizospheric processes strongly affect the release of critical elements from lithium-ion battery black mass. While such mobilization represents an environmental risk in the case of uncontrolled disposal, it also provides insights into chemical processes that may be exploited for the recovery of critical raw materials from secondary resources, contributing to more responsible raw material supply chains.
References
Miśta, G. (2025). Environmental effects of uncontrolled waste disposal: the example of batteries. MSc thesis, University of Wrocław
How to cite: Miśta, G., Pędziwiatr, A., and Potysz, A.: Metal mobilization from lithium-ion battery black mass under rhizospheric conditions: implications for secondary critical raw material recovery , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-12233, 2026.
The increasing demand for lithium has driven a search for alternative extraction sources. Typically, Li+ is extracted from salar brines and hard-rock ores, but recent projects suggest that oilfield-produced waters and geothermal waters might be viable sources as well.[1] One of the challenges associated with extracting Li+ from these alternative sources is the presence of competing ions in much higher concentrations, such as Na+ and Mg2+.[2] Therefore, extraction techniques must be highly selective. Additionally, to extract meaningful amounts of Li+ from these waters, large volumes must be processed.
One approach to the selective adsorption of Li+ from water is the use of crown ethers (CEs).[2] These cyclic structures can exhibit high selectivity for metal ions based on their size, shape, and electrochemical properties. Subsequent desorption of the metal can be achieved by shifting the pH. To make the process more efficient, it would be advantageous to stabilize the crown ethers in a way that makes them easier to extract from the water following the adsorption. Towards this goal, our group successfully synthesized crown ether-functionalized magnetic nanoparticles (MNPs) for the selective adsorption of Li+ from geothermal water. Crown ethers, activated with N-Hydroxysuccinimide (NHS) and N,N’-Dicyclohexylcarbodiimide (DCC) to form an NHS ester, were reacted with aminosilanized MNPs, which were synthesized in a coprecipitation reaction.[3] A stable amide bond was formed, covering the surface of the MNP with crown ethers. The resulting particles were characterized using Raman spectroscopy, dynamic light scattering (DLS) and electron microscopy techniques. In addition, a reactor has been designed which functions to hold the MNP-CEs in place using external magnets as water flows past. This allows for the continual adsorption of Li+ and subsequently, simple extraction of the magnetic host-guest complex from water. By using a pH shift, the Li+ can be desorbed from the CE, and the MNP-CE compound can be reused for further adsorption of additional Li+. First experiments with the prototype reactor have demonstrated that it is possible to hold MNPs in suspension between two external neodymium magnets, with hardly any MNPs being swept out by the flow of the water.
We are currently working to optimize the parameters of the prototype reactor (e.g., magnet placement, water flow rate), and we will perform experiments to determine the adsorption isotherms of the CE-Li+ reaction. In addition, the selectivity of several different CEs for Li+ versus other metal ions will be tested, and the optimal residence time required for sufficient Li+ adsorption will be determined. Further, the stability and reusability of the MNP-CE compound will be assessed. Inductively coupled plasma mass spectrometry (ICP-MS) will be used to determine the concentrations of Li+ and other metal ions in geothermal water before, during and after adsorption experiments.
If successful, our optimization of both the MNP-CE properties and the reactor setup will result in an efficient, environmentally friendly, and scalable extraction method for Li+.
Citations
[1] S. Yang, Y. et al., Nature 2024, 636, 309–321.
[2] I. Oral, S et al., Sep. Purif. Technol. 2022, 294, 121142.
[3] M. Rieger et al. Anal. Bioanal. Chem. 2012, 403, 2529–2540.
How to cite: Kienast, S., Bayer, J., Gleich, B., Ertl, S., Elsner, M., and Seidel, M.: Selective Adsorption of Lithium Ions from Geothermal Water using Crown Ether-Functionalized Magnetic Nanoparticles, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-16850, 2026.
The growing demand for Critical and Strategic Raw Materials (CRMs, SRMs) and the limited availability of primary resources in Europe have renewed regulatory and scientific interest in mine waste and tailings as secondary raw material sources (European Critical Raw Materials Act 2023; Hool et al. 2024). Accordingly, efficient and environmentally sustainable extraction technologies are necessary to minimize both environmental impact and processing costs (Whitworth et al. 2022). Among emerging solutions to conventional acidic leaching, glycine has been attracting attention as a non-toxic and biodegradable amino acid capable of forming stable complexes with calcophile elements under alkaline conditions and low temperatures, enabling low-cost, possible industrial applications for recovering precious and critical metals from mine waste and tailings (O’Connor et al. 2018; Barragán-Mantilla et al. 2024; Eksteen et al. 2018). This study investigated the application of glycine leaching as a green chemical approach for the recovery of copper from fine-grained historical tailings samples from the Fenice–Capanne mine, Tuscany, Italy.
Historical tailings samples were preliminarily characterised in terms of granulometry, geochemical and mineralogical composition using multiple methodologies, such as ICP-MS, HH-XRF, SEM-EDS and SEM-MLA for the definition of metal grades and the identification of metal-bearing minerals. Batch leaching tests were conducted using a glycine solution under controlled conditions, including alkaline pH, a constant liquid-to-solid ratio, and progressively increasing leaching times. The performance of glycine as a lixiviant was evaluated in terms of metal extraction efficiency and selectivity using HH-XRF on solid residues and ICP-OES on leaching liquors. Particular focus was addressed on Cu and associated Zn extraction. As a term of comparison, the same samples were leached using sulphuric acid leaching.
Preliminary results indicated that glycine leaching enabled the selective extraction of Cu and minor Zn while limiting the dissolution of Fe, and competitive recovery rates when compared to traditional sulphuric acid leaching. It highlighted its potential as an environmentally friendly leaching agent. The outcomes of this study could contribute to the assessment of sustainable options for the recovery of CRMs and SRMs from mine tailings within a sustainable and circular economy approach.
How to cite: Baldassarre, G., Zasa Courtial, V., Bellopede, R., and Marini, P.: Selective recovery of copper from mine tailings using a green leaching agent, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19216, 2026.
The continuous development of modern technologies and their constant growth in demand have resulted in a surge in the demand for raw materials since the 20th century. However, a significant portion of the supply still originates from primary sources, which result in significant environmental and social impacts. A substantial part of these environmental problems arise from the production of mine tailings. Simultaneously, the continuous increase in production, development of processing technologies, and increased prices often result in a higher amount of tailings produced per output of target material, due to higher volume extracted jointly with a reduction of the cutoff grade.The EU's Critical Raw Materials Act (CRMA) highlights the strategic importance of 34 critical and 17 strategic raw materials (SRMs), with the latter including copper. To mitigate the environmental and supply risks associated with primary extraction, the development of secondary sources is emphasized. Mine tailings represent a significant potential resource, yet systematic frameworks for their valorization require development. This study addresses this gap through a systematic review of 66 articles on copper processing. By synthesizing this data, it seeks to elucidate how deposit geology and beneficiation processes control tailings composition and, in turn, dictate viable pathways for copper recovery.
This study considers that site dependency stems from predictable geological factors. Accordingly, the original mineralogy is defined by the deposit’s genesis and preservation conditions. This assemblage is then overprinted by the extraction process, which modifies its physical state (e.g., liberation, grind) and changes its surface and bulk chemistry through reagent residues, pH modifiers, and induced oxidation. Finally, long-term storage conditions drive the material’s geochemical evolution through oxidation and secondary mineral formation. The culmination of this pathway is a tailings mineralogical signature that pre-selects feasible recovery processes. The goal of our global data collection is to test this hypothesis by mapping these mineralogical signatures against reported processing outcomes, thereby building a predictive framework for route selection for copper reprocessing from mine tailings.
The analysis defends an integrated, site-adjusted framework where the predictive power of deposit geology and tailings mineralogy guides initial process screening but must be tested against four viability criteria: the ability to generate a marketable concentrate, adaptation to local constraints (climate, water, infrastructure), sufficiency of data for design, and a recalibrated economic model that incorporates pollution abatement costs as value drivers, not externalities. To overcome data gaps and extreme site-specificity, success depends on building a global library of mineralogical analogues using advanced characterization (e.g., automated mineralogy, hyperspectral sensing), enabling the extrapolation of proven flowsheets to new sites. This synergetic approach, valuing environmental and social risk reduction alongside metal valorization, is essential to transform tailings from a liability into a strategically viable, circular resource, reducing the pressure on raw material supply chains.
How to cite: Elias, M., Panepinto, D., Bellopede, R., and Zanetti, M.: Mineralogical control and economic barriers for tailings reprocessing, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-12761, 2026.
In line with the EU Green Deal and strategic policies on critical raw materials (CRMs), the sustainable management of extractive waste is a major challenge for Europe. To address this, the Decision Support Tool for Sustainable Resource Management (DST-SRM) has been developed as a digital platform enabling the assessment of alternative scenarios for extractive waste (EW) valorisation.
The DST-SRM tool integrates geological, environmental, and economic datasets and applies Multicriteria Decision Analysis (MCDA) to identify potential resources by assessing significant quantities of unexploited minerals and associated by-products. It enables the development of multiple scenarios, the selection of traditional and/or advanced processing techniques for each scenario, and the comparison of scenario outcomes to identify the most sustainable solution. Each scenario is defined through a flowchart that specifies, for each activity, the machinery and equipment used with the relevant technical specifications, the quantities of material processed, and the resulting products or waste. Based on these data and site-specific information, the environmental, economic, and social impacts are assessed using quantitative and semi-quantitative approaches for each scenario.
The Montorfano granite quarry, located in northern Italy, was selected as a case study for DST-SRM validation. This quarry has large deposits of mining waste (covering 200,000 m²), now authorised as a mining site for the exploitation of RM to feed a dedicated treatment plant (approximately 140,000 t/year). Site-specific data included geological and hydrogeological data, chemical and mineralogical composition (55% feldspar, 40% silica, 5% mica), and waste size distribution. Site-specific data also includes characterisation of the area surrounding the extraction site (populated areas, transport routes, distances to facilities, etc.).
Nine scenarios were simulated, ranging from in situ remediation (capping) to advanced secondary recovery techniques, including magnetic separation and dust treatment. The results indicate that the most sustainable option corresponds to the company’s current operating practice, represented by the final scenario evaluated, which achieves the best balance among environmental, economic, and social performance.
Continuous process improvement, together with the recovery and commercialisation of all end products and strategic market diversification, enables the company to maximise economic returns while reducing environmental and social impacts. In this context, the implementation of effective dust extraction systems not only enhances workers’ health and safety but also allows the recovered dust to be valorised as a marketable product.
The Montorfano case study confirms the DST-SRM’s ability to support inclusive, evidence-based decision-making and represents a starting point for operators and stakeholders, promoting extractive waste valorisation within a circular economy by transforming environmental liabilities into strategic secondary resources.
Keywords: Decision Support Tool, Critical Raw Materials, Extractive Waste, Circular Economy, Sustainable mining
How to cite: Mancini, S., Faraudello, A., Casale, M., Cacciolo, F., Rossi, P., Cazzaniga, A., Mister, I., Menso, I., and Dino, G. A.: A Decision-Support Approach to the Sustainable Management of Extractive Waste: Application of the DST-SRM Tool to the Montorfano Case Study, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-12117, https://doi.org/10.5194/egusphere-egu26-12117, 2026.
In the framework of the European Green Deal and circular economy strategies, the sustainable management of Municipal Solid Waste Incineration (MSWI) residues has emerged as a key challenge. Bottom Ash (BA) represents a significant volume of these residues and is a valuable source of secondary raw materials (SRMs) and Critical Raw Materials (CRMs). Conventional regulatory assessments often focus on bulk chemical composition, which can overestimate environmental risks, such as the HP14-ecotoxic property, by assuming that heavy metals are present in their most reactive and bioavailable oxidised forms.
This study presents an integrated, multi-technique analytical workflow designed to bridge the gap between total elemental concentration and actual environmental risk through speciation-based assessment. By employing a controlled-density separation procedure using LST Fastfloat, distinct density classes were successfully fractionated: a light fraction containing plastics and organic matter; a medium fraction containing glassy blebs and silicates; and a heavy fraction containing metallic alloys and ferrous materials.
To achieve a rigorous scientific characterisation of these fractions, a synergistic multi-technique approach was employed. While SEM-EDX provided high-resolution morphological data and localised chemical speciation – revealing that metals like Zn, Cu and Pb are frequently hosted within metallic alloys rather than oxides – X-Ray Powder Diffraction (XRPD) was crucial for identifying the crystalline mineralogical assemblages. XRPD analysis allowed to confirm the incorporation of heavy metals into stable metallic phases or inert silicate matrices, significantly limiting their mobility and environmental impact under standard conditions.
The quantitative chemical framework was further refined by integrating Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) with Total Reflection X-Ray Fluorescence (T-XRF). The utilisation of ICP-OES was instrumental to ensuring regulatory-grade accuracy in the bulk chemical characterisation; by providing a precise total elemental inventory, it facilitated a direct comparison between the total concentration of heavy metals and their actual mineralogical sequestration as identified by SEM-EDX and XRPD. Simultaneously, T-XRF – characterized by its high sensitivity and minimal sample volume requirements – provided precise quantification of trace elements and a fundamental cross-validation of the wet-chemical results obtained via ICP-OES after microwave-assisted mineralisation. These integrate analyses demonstrates that the heavy metal content is predominantly sequestered in stable, non-reactive phases – such as metal alloys and glassy blebs. These findings have significant implications for the reclassification of BA from hazardous to non-hazardous waste. This research provides a scientifically robust workflow method to characterize BA precisely, thereby reducing their disposal cost and enabling reuse as secondary raw materials.
How to cite: Passavia, C., Colonna, M., Parlapiano, F., Stoppa, F., and Rosatelli, G.: From waste to resource: multi-technique metal speciation and mineralogical characterisation of incinerator bottom ash for circular economy applications, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7337, https://doi.org/10.5194/egusphere-egu26-7337, 2026.
The 2021 Tajogaite eruption (La Palma, Canary Islands) produced large volumes of volcanic ash that represent an underutilized aluminosilicate resource. Representative ash samples are rich in SiO₂ and Al₂O₃ and show a low Si/Al ratio (~2.5), making them promising precursors for low-silica zeolites with high cation density and strong affinity for polar molecules such as CO₂—properties of interest for direct air capture (DAC).
Here we investigate a conversion route from Tajogaite ash to zeolitic adsorbents and assess their suitability for CO₂ capture. The synthesis follows an alkaline fusion–hydrothermal approach: ash is fused with NaOH at >400 °C for varying times, the fusion product is dissolved to form an aluminosilicate gel, and hydrothermal crystallization is carried out at different temperatures over a range of crystallization times to steer phase selectivity.
X-ray diffraction is used to track zeolite crystallization and phase evolution (e.g., FAU-type zeolite X at shorter times versus sodalite-type phases at longer times), while BET surface area/porosity, thermogravimetric analysis, and CO₂ adsorption isotherms are used to quantify accessible microporosity, thermal/regeneration stability, and CO₂ uptake/affinity in DAC-relevant conditions.
To efficiently optimize performance and resource intensity (e.g., alkali usage, fusion/crystallization conditions), we implement a structured Design of Experiments (DoE) workflow: an initial screening stage using fractional factorial designs to identify the most influential synthesis factors, followed by response surface methodology to locate optimal operating windows for maximizing low-pressure CO₂ adsorption while maintaining robust regenerability.
Overall, this work links volcanic ash valorization with carbon management, advancing locally sourced sorbents for DAC within a circular-economy framework relevant to energy, resources, and environmental sustainability.
How to cite: Signorelli, L., E. Hernández-Gutiérrez, L., M. Pérez, N., A. Hernández, P., Padrón, E., Esparza, P., and Hernández-Martín, H.: Zeolites synthesis from Tajogaite eruption ash (La Palma, Canary Islands) and its performance for CO2 capture, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-14815, 2026.
Electric Arc Furnace Dust (EAFD) is a byproduct of steel production in electric arc furnaces (EAF). With an annual production of approximately 5-10 million tons, EAFD represents a significant challenge for both the steel industry and the environment. Currently, only ~30% of EAFD is utilized for recovery of metals (mainly Zn), while the remaining 70% is landfilled. The reuse of EAFD is essential for greener and more sustainable steel production. One potential application of EAFD is to be used as an adsorbent for phosphate removal due to its high Fe content.
The focus of this study was the characterization of EAFD magnetic fraction enriched in iron-related phases and depleted in other heavy metals using a range of analytical techniques including X-Ray Diffraction (XRD), Mössbauer spectroscopy, Transmission Electron Microscopy (TEM), Fourier Transformed Infrared Spectroscopy (FTIR) and N2 adsorption/desorption analysis. To validate its usage as an adsorbent, we functionalized EAFD to enhance its reactivity towards phosphates. Functionalization was achieved via a dissolution (1 M HCl) followed by recrystallization through precipitation with either 5M NaOH or Ca(OH)2 until pH reached 7, according to the method described by Fu et al. (2018). Functionalized materials were characterized regarding their physicochemical properties and applied in phosphate adsorption experiments.
Phase composition analysis using XRD and Mössbauer spectroscopy revealed a mixture of iron minerals, including magnetite, hematite, franklinite, and nano-maghemite with additional quartz and calcite. In both NaOH (Fr-Na) and Ca(OH)2 (Fr-Ca) precipitated materials, ferrihydrite was detected among the iron phases. Its formation was linked with the disappearance of franklinite and a slight decrease in magnetite content. Additionally, Fr-Na material was depleted of calcite. TEM images confirmed the presence of ferrihydrite coating on the functionalized materials. FTIR spectra of all the samples exhibited intensive bands at 637, 570 and 440 cm-1 corresponding to Fe-O and Fe-OH stretching vibrations. EAFD and Fr-Ca showed additional strong bands at 1445 and 875 cm-1, attributed to C-O stretching vibrations of carbonate anions. The absence of these bands in Fr-Na is consistent with the disappearance of calcite observed in the XRD pattern. Functionalization resulted in a sevenfold increase in specific surface area (10 → 70 m2/g), creating many new adsorption sites.
Adsorption studies confirmed the enhanced reactivity of functionalized materials towards phosphates. The Fr-Ca material exhibited the best performance under all tested conditions, with its adsorption capacity increasing fivefold from 2 to 10 mg/g compared to raw EAFD. Moreover, functionalization led to a longer time required to reach adsorption equilibrium (from approximately 20 minutes to over 2 hours), which is attributed to phosphate diffusion within the nanometric pore system of the ferrihydrite coating.
The simplicity of the functionalization process, combined with the substantial increase in adsorption capacity, highlights EAFD as a promising adsorbent for phosphate immobilization. Its wide availability and magnetic properties further support its applicability, especially compared to the current practice of landfilling.
This work was supported by the National Science Centre (Poland) (grant number 2021/41/B/NZ9/01552).
How to cite: Czeremuga, J., Skalny, M., and Bajda, T.: Electric Arc Furnace Dusts characterization, functionalization and potential applications, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-13813, 2026.
The complexity and increasingly intricate nature of global industrial value chains is a challenge to transparency and due diligence. From the US Dodd-Frank Act enacted in 2010 (currently under revision), via the OECD and Chinese Due Diligence Guidances to the 2024 EU Directive on corporate sustainability due diligence, national and supranational legislation has reinforced control on the provenance of critical raw materials and fostered the need for traceability approaches. The EU project MaDiTraCe (2023-2026, https://www.maditrace.eu), develops synergies between digital product traceability solutions, material fingerprinting (MFP), using the intrinsic properties of CRMs and derived intermediate and final products, and artificial tagging. Four commodities, crucial for batteries and magnet value chains, are targeted: cobalt, lithium, natural graphite and rare earths. Here we present an overview on the MFP approach of the project with a special focus on lithium, throughout its value chains, from lithium deposits (hard rocks, salars, geothermal fluids) to batteries. A wide range of on-site and lab-based analytical techniques has been tested on reference samples of ores, concentrates and products and evaluated for their discriminatory power when combined with advanced data analysis. Implementation of this novel, hybrid approach including digital and material technology into the CERA 4in1 mineral raw material certification (https://www.maditrace.eu/cera4in1) system is underway.
How to cite: Kloppmann, W., Moradell Casellas, A., Losno, D., Anne-Marie, D., Quentin, D., Arato, R., Shang, Y., and Monfort Climent, D.: Material fingerprinting of critical raw materials as part of an integrated approach towards due diligence certification: the MaDiTraCe project, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19788, 2026.
With the ongoing green transition and current geopolitical instabilities, the EU has increased focus on domestic sources of critical metals (CM), including secondary resources such as abandoned mine waste. As part of the FutuRaM project (101058522) to establish methodologies to better understand waste streams of secondary raw materials in the EU, several former mine waste repositories studied for secondary raw material potential. The abandoned Bäckegruvan Fe ± Cu mine tailings, in the Bergslagen mining district of southern central Sweden, provide a case study for examination of critical metal potential in mine waste.
As part of a Swedish governmental directive, surficial sampling of abandoned mine waste was conducted throughout Sweden, which demonstrated Bäckegruvan contained high levels of Co and rare earths (REE) withing the tailings. Further investigations, including additional sampling, drilling at depth provided several hundred samples to quantify the potential resources at Bäckegruvan. Bulk geochemical analyses of the collected samples for CM identified average concentrations of 610 ppm Co and 1479 ppm REE within the tailings. Combining these data with advanced geophysical surveys to calculate volume enabled the conservative estimate of 5,700 tonnes of REE and 1200 tonnes of Co in the 5.3 Mt of tailings (Camitz et al., 2024).
The estimates provided in (Camitz et al., 2024) do not consider the importance of mineralogy when considering extractive potential. Investigations of select samples were conducted using SEM-EDS and XRD. These methods identified numerous host phases for REE, where the most abundant included törnebohmite, and gadolinite-Ce which lack economic recovery methods. Minor bastnäsite, allanite, monazite and xenotime were observed. Only rare, small grains of Co-bearing mineral phases (e.g. cobaltite ) were identified in the samples. SEM-EDS identified pyrrhotite as the predominant host of Co, with concentrations between 0.2 - 2.0 wt%. In pyrrhotite Co likely occurs as lattice substitution, while the higher weight percentages may indicate nano-scale inclusions of Co-minerals in the pyrrhotite. Similar “missing” Co has been observed in pyrrhotite at the Zinkgruvan mine in Bergslagen (Hjorth, 2022). This makes any recovery of Co from this mine waste uneconomic.
This study has demonstrated that, despite apparently promising levels of REE and Co shown by geochemical analysis at Bäckegruvan, at present economic recovery is unlikely. With the focus on EU domestic production of CM resources as laid out in the Critical Raw Materials Act, including re-mining of secondary resources, this study reinforces the need for detailed studies of mine waste for geological feasibility before inclusion in any national resource estimate, or strategic stockpile.
References:
Camitz, J., Rauséus, G., Jönberger, J., Persson, L., Sopher, D., & Bastani, M. (2024). Secondary resources directive: Characterisation of mining waste in central and southern Bergslagen, Sweden (SGU-rapport 2024:03). Sveriges Geologiska Undersökning.
Hjorth, I. (2022). Characterization of the cobalt content in zinc ore from Zinkgruvan, Sweden (Master’s thesis, Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering). DiVA – Digitala Vetenskapliga Arkivet.
How to cite: Casey, P., Ladenberger, A., and Arvidsson, R.: The occurrence of critical metals in mine waste: not all that glitters is gold - a case study from the Bäckegruvan Fe-Cu mine tailings, Bergslagen, Sweden, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-16002, 2026.
Posters virtual: Tue, 5 May, 14:00–14:03 | vPoster spot 4
EGU26-1384 | Posters virtual | VPS19
Fingerprints of Nickel Exploration in the Pulivendla-Vemula (P-V) sill in Cuddapah Basin:Geological Complexity and Discovery PotentialTue, 05 May, 14:00–14:03 (CEST) vPoster spot 4
The increasing global demand for nickel, driven by its critical role in stainless steel production and emerging battery minerals technologies, has intensified exploration efforts in geologically diverse terrains. This study focuses on the Cuddapah Basin, a Proterozoic sedimentary basin in southern India, which presents a complex geological framework with promising yet underexplored potential for nickel mineralization. Through an integrated approach combining lithological mapping, geophysical surveys, and geochemical analysis, this paper present fingerprints of geochemical and geophysical signatures to target Nickel Exploration. The preliminary findings indicate the presence of ultramafic intrusions and favourable host rocks such as picritic sills which are typically associated with nickel sulfide deposits. The western margin of the Proterozoic-aged Cuddapah Basin contains gabbro and plagioclase bearing sills within the Tadapathri formations These sills have 4-28% MgO and 30-1050ppm Ni and they are characterized by elevated Th/Nb which is indicative of contamination by upper crustal material. The low MgO mafic magmas have one to two orders of magnitude viscosity higher than the picritic sill they are emplaced all along the Cuddapah basin margin. No Ni-Sulphide mineralization is known in this belt, but trace interstitial sulphide is present. The following features of the Pulivendla-Vemula sill complex indicate that the rocks are prospective for magmatic sulfide exploration:1. Tholeiitic lavas and sills were emplaced during extensional intra-cratonic rifting at a time of major Ni ore formation at ~1.9 Ga metallogenic epoch i.e late Proterozoic-Archaean in age.2. Un-deformed fresh differentiated ultramafic sills have a range in Ni concentration over a narrow interval of forsterite content with primary olivine 3. These sills and other sills in the footprint of regional magnetic and gravity anomalies possibly contain feeders where immiscible magmatic sulfides may have formed. correlating between Werner depth estimations and seismic data, particularly in pinpointing fault zones. These zones act as critical conduits for fluid migration from the mantle to the surface, playing a vital role in both tectonic interpretation and mineralexploration4. Despite the absence of magmatic sulfide mineralization and magmatic breccias, there is untested potential within the basin stratigraphy for the development of intrusions which have a magnetic and density signal, possibly in association with a structural break as well as a diagnostic electromagnetic signal from highly conductive sulfide mineralization. However, the geological complexity, including structural deformation and metamorphic overprints, poses significant challenges in locating economically viable deposits. The study underscores the importance of advanced exploration techniques and multidisciplinary data integration to improve discovery success rates. Ultimately, this work contributes valuable insights into the Ni-mineral prospectivity of the P-V Picritic Sill in western margin of Cuddapah Basin and highlights its potential as a frontier region to relook for nickel exploration in India.
How to cite: Sunder Raju, P. V.: Fingerprints of Nickel Exploration in the Pulivendla-Vemula (P-V) sill in Cuddapah Basin:Geological Complexity and Discovery Potential, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-1384, https://doi.org/10.5194/egusphere-egu26-1384, 2026.
EGU26-9067 | ECS | Posters virtual | VPS19
Safety and Sustainability in Artisanal and Small-Scale Mining Operations in MozambiqueTue, 05 May, 14:03–14:06 (CEST) vPoster spot 4
Artisanal and small-scale mining (ASM) is an important source of livelihood in Mozambique, directly involving over 100,000 people, largely through informal and poorly regulated operations (Delve, 2020). ASM activities are concentrated in provinces with high mineral potential, including Manica, Tete, Zambézia, Niassa, Nampula and Cabo Delgado (Mapurango, 2014), and primarily involve the extraction of gold, precious and semi-precious stones, as well as construction materials. Despite its socio-economic relevance, the sector is characterised by weak technical organisation, limited regulatory integration and widespread informality.
This study examines the main safety and sustainability challenges associated with ASM in Mozambique, with particular emphasis on occupational health and safety and environmental management. The methodological approach is based on a review of secondary literature and documentary analysis of existing legal and policy frameworks. The analysis indicates that high levels of informality contribute to unsafe working conditions, inadequate use of personal protective equipment, frequent occupational accidents and significant environmental degradation, including soil and water contamination.
Recent regulatory interventions, such as the suspension of mining licences in Manica Province in October 2025 due to uncontrolled discharge of mining effluents, highlight the urgency of strengthening environmental governance and enforcement mechanisms. The results suggest that the adoption of sustainable mining principles—focused on risk management, environmental protection, decent working conditions and long-term economic viability—can substantially improve the performance of ASM operations. Practical measures include basic technical training, increased awareness campaigns on occupational health and safety, gradual adoption of appropriate technologies and progressive formalization supported by effective monitoring.
In conclusion, enhancing safety and sustainability in ASM is essential not only to reduce occupational and environmental risks but also to ensure that small-scale mining continues to positively contribute to local communities and the national economy.
How to cite: dos Santos, L. V. S., Guiliche, M. E., and Mugabe, J. A.: Safety and Sustainability in Artisanal and Small-Scale Mining Operations in Mozambique, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-9067, https://doi.org/10.5194/egusphere-egu26-9067, 2026.
