Abstracts
Abstract
Many exploration companies are now focusing on specialty materials that are associated with so-called ‘green technology’. These include ‘battery materials’, ‘magnet materials’ and ‘photovoltaic materials’, and many such commodities are also broadly labelled as ‘critical materials’ because they are seen as vital for industrial development, societal needs or national security. The definitions used for such materials are not always consistent among jurisdictions or across industry, and this paper attempts to clarify the criteria and address some common misconceptions. The distinction between major minerals (e.g. base metals) and ‘specialty materials’ (i.e. those mined or produced in much smaller amounts) is particularly important.
The markets for many specialty materials are growing faster than those for traditional ferrous, precious and base metals and they are often portrayed as excellent long-term investment opportunities. However, the small market bases for specialty materials and considerable uncertainty around growth projections (especially related to material substitutions and rapid technological change) need to be taken into consideration for objective assessment of the development potential of any proposed project, establishment of new supply chains by major corporations, and responsible decision-making (mineral policy) by government. In the short-term, projects aimed at specialty materials (materials with a small market base) cannot benefit from economy of scale, and their development hinges on commercially proven metallurgical processes, unless they are supported by governments or end-users.
Several specialty metals (e.g. germanium, indium, cadmium, and cobalt) are commonly obtained as by-product of base metal extraction. In such cases, systematic testing of base metal ores for their specialty metal content may justify the addition of relevant recovery circuits to existing smelters. If positive results are obtained, the need for targeting new sources of such specialty metals as primary exploration targets may be reduced or eliminated.
Where market conditions permit and concerns about the future availability of materials seem reliable, grass-roots exploration for specialty materials is warranted, and pre-competitive government involvement may be justified to promote such development efforts.
Keywords:
- Battery,
- Cobalt,
- Critical Materials,
- Exploration,
- Magnet,
- Market,
- Photovoltaic,
- Rare Earth Elements,
- Resources
Résumé
De nombreuses sociétés d'exploration se concentrent désormais sur les matériaux spécialisés associés à ce que l'on appelle la « technologie verte ». Ceux-ci incluent les « matériaux pour batterie », les « matériaux magnétiques » et les « matériaux photovoltaïques », et de nombreux produits de ce type sont aussi largement étiquetés comme « matériaux critiques » car ils sont considérés comme vitaux pour le développement industriel, les besoins sociétaux ou la sécurité nationale. Les définitions utilisées pour ces matériaux ne sont pas toujours cohérentes entre les juridictions ou dans l'industrie, et ce document tente de clarifier les critères et de répondre à certaines idées fausses courantes. La distinction entre les principaux minéraux (par exemple les métaux de base) et les « matériaux spécialisés » (c'est-à-dire ceux extraits ou produits en quantités beaucoup plus faibles) est particulièrement importante.
Les marchés de nombreux matériaux spécialisés croissent plus rapidement que ceux des métaux ferreux, précieux et de base traditionnels et ils sont souvent présentés comme d'excellentes opportunités d'investissement à long terme. Cependant, le marché restreint des matériaux spécialisés et l'incertitude considérable entourant les projections de croissance (en particulier liées aux substitutions de matériaux et aux changements technologiques rapides) doivent être pris en considération pour une évaluation objective du potentiel de développement de tout projet proposé, l'établissement de nouvelles chaînes d'approvisionnement par les grandes entreprises et une prise de décisions responsable par le gouvernement (politique minière). À court terme, les projets visant des matériaux spécialisés (matériaux ayant un marché restreint) ne peuvent pas bénéficier d'économies d'échelle et leur développement repose sur des procédés métallurgiques commercialement éprouvés, à moins qu'ils ne soient soutenus par les gouvernements ou les utilisateurs finaux.
Plusieurs métaux spécialisés (par exemple le germanium, l'indium, le cadmium et le cobalt) sont couramment obtenus comme sous-produits de l'extraction des métaux de base. Dans de tels cas, l'analyse systématique des minerais de métaux de base pour leur teneur en métaux spécialisés peut justifier l'ajout de circuits de récupération adéquats aux fonderies existantes. Si des résultats positifs sont obtenus, la nécessité de cibler de nouvelles sources de ces métaux spécialisés en tant que cibles d'exploration primaires peut être réduite ou éliminée.
Lorsque les conditions du marché le permettent et que les craintes quant à la disponibilité future des matériaux semblent fiables, l'exploration primaire de matériaux spécialisés est justifiée, et la participation préconcurrentielle du gouvernement peut être justifiée pour promouvoir de tels efforts de développement.
Download the article in PDF to read it.
Download
Appendices
Bibliography
- Anonymous, 1999, Fuel cells meet big business: Economist, v. 352, no. 8219, p. 59–60.
- Auerbach, R., Bokelmann, K., Stauber, R., Gutfleisch, O., Schnell, S., and Ratering, S., 2019, Critical raw materials–Advanced recycling technologies and processes: Recycling of rare earth metals out of end of life magnets by bioleaching with various bacteria as an example of an intelligent recycling strategy: Minerals Engineering, v. 134, p. 104–117, https://doi.org/10.1016/j.mineng.2018.12.022.
- Baker, I., 2018, Rare Earth magnets, in Baker, I., ed., Fifty Materials That Make the World: Springer, Cham, p. 187–194, https://doi.org/10.1007/978-3-319-78766-4.
- Borst, A.M., Smith, M.P., Finch, A.A., Estrade, G., Villanova-de-Benavent, C., Nason, P., Marquis, E., Horsburgh, N.J., Goodenough, K.M., Xu, C. , Kynický, J., and Geraki, K., 2020, Adsorption of rare earth elements in regolith-hosted clay deposits: Nature Communications, v. 11, 4386, https://doi.org/10.1038/s41467-020-17801-5.
- Braga, A.F.B., Moreira, S.P., Zampieri, P.R., Bacchin, J.M.G., and Mei, P.R., 2008, New processes for the production of solar-grade polycrystalline silicon: A review: Solar Energy Materials and Solar Cells, v. 92, p. 418–424, https://doi.org/10.1016/j.solmat.2007.10.003.
- Brainard, J., Nassar, N.T., Gambogi, J., Baker, M.S., and Jarvis, M.T., 2018, Globally sourced mineral commodities used in U.S. Navy SEAL gear—An illustration of U.S. net import reliance (ver. 2.0, January 2018): U.S. Geological Survey General Information Product 183, https://doi.org/10.3133/gip183.
- Bresser, D., Hosoi, K., Howell, D., Li, H., Zeisel, H., Amine, K., and Passerini, S., 2018, Perspectives of automotive battery R&D in China, Germany, Japan, and the USA: Journal of Power Sources, v. 382, p. 176–178, https://doi.org/10.1016/j.jpowsour.2018.02.039.
- Chediak, M., 2018, Big battery boom hits another roadblock: Fire-fearing cities [Technology news]: BloombergQuint, https://www.bloombergquint.com/technology/the-big-battery-boom-hits-another-roadblock-fire-fearing-cities. Accessed: May 18, 2020.
- Chigondo, F., 2018, From metallurgical-grade to solar-grade silicon: an overview: Silicon, v. 10, p. 789–798. https://doi.org/10.1007/s12633-016-9532-7.
- Clarke, G., Northcote, B., Katay, F., and Tombe, S.P., 2021, Exploration and Mining in British Columbia, 2020: A summary: Provincial Overview of Exploration and Mining in British Columbia, 2020, British Columbia Ministry of Energy, Mines and Low Carbon Innovation, Geological Survey Information Circular 2021-01, p. 1–45, http://cmscontent.nrs.gov.bc.ca/geoscience/PublicationCatalogue/InformationCircular/BCGS_IC2021-01-01.pdf. Accessed: April 5, 2021.
- Cui, J., Kramer, M., Zhou, L., Liu, F., Gabay, A., Hadjipanayis, G., Balasubramanian, B., and Sellmyer, D., 2018, Current progress and future challenges in rare-earth-free permanent magnets: Acta Materialia, v. 158, p. 118–137, https://doi.org/10.1016/j.actamat.2018.07.049.
- Darghouth, A., Aouida, S., and Bessais, B., 2021, High purity porous silicon powder synthesis by magnesiothermic reduction of Tunisian silica sand: Silicon, v. 13, p. 667–676, https://doi.org/10.1007/s12633-020-00433-1.
- Davidsson, S., and Höök, M., 2017, Material requirements and availability for multi-terawatt deployment of photovoltaics: Energy Policy, v. 108, p. 574–582, https://doi.org/10.1016/j.enpol.2017.06.028.
- Delfeld, C.T., 2018, How to profit from the commodity market’s blind spot: Alquimista Assets Special Report, http://cdn.ceo.ca.s3-us-west-2.amazonaws.com/1ea2dtt-Delfeld-Report-2019.pdf.
- European Commission, 2014, Report on critical raw materials for the EU: Report of the Ad hoc Working Group on defining critical raw materials, 41 p., http://litio.ipg.pt/wp-content/uploads/2018/07/EC_crm-report-on-critical-raw-materials_2014.pdf. Accessed: August 8, 2021.
- European Commission, 2017, Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions on the 2017 list of Critical Raw Materials for the EU: European Commission, Document 52017DC0490, 8 p., https://ec.europa.eu/transparency/regdoc/rep/1/2017/EN/COM-2017-490-F1-EN-MAIN-PART-1.PDF. Accessed: May 15, 2021.
- European Commission, 2018, Report on raw materials for battery applications, 47 p., https://ec.europa.eu/transport/sites/transport/files/3rd-mobility-pac99k/swd20180245.pdf. Accessed: May 15, 2021.
- European Commission, 2020, Critical raw materials resilience: Charting a path towards greater security and sustainability: Communication from the Commission to the Council, the European Parliament, the European Economic and Social Committee and the Committee of the Regions – Commission of the European Communities – COM 474, Document 52020DC0474, https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:52020DC0474.
- Evans, K., 2014, Lithium; in Gunn, G., ed., Critical Metals Handbook, Chapter 10: John Wiley and Sons, p. 230–260, https://doi.org/10.1002/9781118755341.ch10.
- Fishman, T., and Graedel, T.E., 2019, Impact of the establishment of US offshore wind power on neodymium flows: Nature Sustainability, v. 2, p. 332–338, https://doi.org/10.1038/s41893-019-0252-z.
- Flanagan, D.M., 2021, Copper, Mineral Commodity Summaries: United States Geological Survey, p. 52–53, https://pubs.usgs.gov/periodicals/mcs2021/mcs2021.pdf.
- Fortier, S.M., Nassar, N.T., Mauk, J.L., Hammarstrom, J.M., Day, W.C., and Seal, R.R., 2020, USGS critical minerals review: Mining Engineering, v. 72, p. 30–45.
- Fraunhofer Institute for Solar Energy Systems, 2020, Photovoltaics Report: Fraunhofer ISE, https://www.ise.fraunhofer.de/content/dam/ise/de/documents/publications/studies/Photovoltaics-Report.pdf. Accessed: March 19.2021.
- Frenzel, M., Mikolajczak, C., Reuter, M.A., and Gutzmer, J., 2017, Quantifying the relative availability of high-tech by-product metals – The cases of gallium, germanium and indium: Resources Policy, v. 52, p. 327–335, https://doi.org/10.1016/j.resourpol.2017.04.008.
- Gambogi, J., 2020, Rare Earths, Mineral Commodity Summaries: United States Geological Survey, p. 132–133, https://pubs.usgs.gov/periodicals/mcs2020/mcs2020.pdf.
- Gambogi, J., 2021a, Rare Earths, Mineral Commodity Summaries: United States Geological Survey, p. 132–133, https://pubs.usgs.gov/periodicals/mcs2021/mcs2021.pdf.
- Gambogi, J., 2021b, Yttrium, Mineral Commodity Summaries: United States Geological Survey, p. 186–187, https://pubs.usgs.gov/periodicals/mcs2021/mcs2021.pdf.
- Geuss, M., 2018, Toyota’s new magnet won’t depend on some key rare-earth minerals [Posted February 28]: Ars Technica, https://arstechnica.com/cars/2018/02/neodymium-more-like-neo-dont-mium-new-magnet-uses-fewer-key-rare-earths/.
- Goodenough, K.M., Wall, F., and Merriman, D., 2018, The rare earth elements: Demand, global resources, and challenges for resourcing future generations: Natural Resources Research, v. 27, p. 201–216.
- Gourcerol, B., Gloaguen, E., Melleton, J., Tuduri, J., and Galiegue, X., 2019, Re-assessing the European lithium resource potential – A review of hard-rock resources and metallogeny: Ore Geology Reviews, v. 109, p. 494–519, https://doi.org/10.1016/j.oregeorev.2019.04.015.
- Government of Canada, 2021, Canada Announces Critical Minerals List: https://www.canada.ca/en/natural-resources-canada/news/2021/03/canada-announces-critical-minerals-list.html. Accessed: May 15, 2021.
- Green, M.A., Emery, K., Hishikawa, Y., Warta, W., and Dunlop, E.D., 2015, Solar cell efficiency tables (Version 45): Progress in Photovoltaics: Research and Applications, v. 23, p. 1–9, https://doi.org/10.1002/pip.2573.
- Green Car Congress, 2019, Adamas: NCM 811 is now the second-most used cathode chemistry in China’s passenger EV market [Posted November 15]: BioAge Group LLC, https://www.greencarcongress.com/2019/11/20191115-admas.html. Accessed: July 15, 2021.
- Grunditz, E.A., Lundmark, S.T., Alatalo, M., Thiringer, T., and Nordelöf, A., 2018, Three traction motors with different magnet materials – Influence on cost, losses, vehicle performance, energy use and environmental impact: 2018 Thirteenth International Conference on Ecological Vehicles and Renewable Energies (EVER), p. 1–13, https://doi.org/10.1109/EVER.2018.8362387.
- Guney, M.S., and Tepe, Y., 2017, Classification and assessment of energy storage systems: Renewable and Sustainable Energy Reviews, v. 75, p. 1187–1197, https://doi.org/10.1016/j.rser.2016.11.102.
- Hayes, S.M., and McCullough, E.A., 2018, Critical minerals: A review of elemental trends in comprehensive criticality studies: Resources Policy, v. 59, p. 192–199, https://doi.org/10.1016/j.resourpol.2018.06.015.
- Heath, G.A., Silverman, T.J., Kempe, M., Deceglie, M., Ravikumar, D., Remo, T., Cui, H., Sinha, P., Libby, C., Shaw, S., Komoto, K., Wambach, K., Butler, E., Barnes, T., and Wade, A., 2020, Research and development priorities for silicon photovoltaic module recycling to support a circular economy: Nature Energy, v. 5, p. 502–510, https://doi.org/10.1038/s41560-020-0645-2.
- Höll, R., Kling, M., and Schroll, E., 2007, Metallogenesis of germanium—A review: Ore Geology Reviews, v. 30, p. 145–180, https://doi.org/10.1016/j.oregeorev.2005.07.034.
- Hummel, P., Lesne, D., Radlinger, J., Golbaz, C., Langan, C., Takahashi, K., Mulholland, D., Stott, A., Haire, G., Mittermaier, M., Gaudois, N., and Shaw, L., 2017, UBS Evidence Lab electric car teardown – Disruption ahead?: Report, UBS Limited, https://neo.ubs.com/shared/d1wkuDlEbYPjF/.
- Hund, K., La Porta, D., Fabregas, T.P., Laing, T., and Drexhage, J., 2020, Minerals for climate action: The mineral intensity of the clean energy transition: World Bank Group, Washington, DC, 112 p., https://pubdocs.worldbank.org/en/961711588875536384/Minerals-for-Climate-Action-The-Mineral-Intensity-of-the-Clean-Energy-Transition.pdf.
- International Energy Agency, 2017, Energy technology perspectives 2017: International Energy Agency Directorate of Sustainability, Technology and Outlooks, 441 p., https://iea.blob.core.windows.net/assets/a6587f9f-e56c-4b1d-96e4-5a4da78f12fa/Energy_Technology_Perspectives_2017-PDF.pdf. Accessed: May 15, 2021.
- Kesler, S.E., Gruber, P.W., Medina, P.A., Keoleian, G.A., Everson, M.P., and Wallington, T.J., 2012, Global lithium resources: Relative importance of pegmatite, brine and other deposits: Ore Geology Reviews, v. 48, p. 55–69, https://doi.org/10.1016/j.oregeorev.2012.05.006.
- Küpper, D., Kuhlmann, K., Wolf, S., Pieper, C., Xu, G., and Ahmad, J., 2018, The future of battery production for electric vehicles: Boston Consulting Group, September 18, 2018, https://www.bcg.com/en-ca/publications/2018/future-battery-production-electric-vehicles.aspx.
- Leader, A., Gaustad, G., and Babbitt, C., 2019, The effect of critical material prices on the competitiveness of clean energy technologies: Materials for Renewable and Sustainable Energy, v. 8, 8, https://doi.org/10.1007/s40243-019-0146-z.
- Lin, S.-L., Huang, K.-L., Wang, I.-C., Chou, I-C., Kuo, Y.-M., Hung, C.-H., and Lin, C., 2016, Characterization of spent nickel–metal hydride batteries and a preliminary economic evaluation of the recovery processes: Journal of the Air & Waste Management Association, v. 66, p. 296–306, https://doi.org/10.1080/10962247.2015.1131206.
- Louwen, A., van Sark, W., Schropp, R., and Faaij, A., 2016, A cost roadmap for silicon heterojunction solar cells: Solar Energy Materials and Solar Cells, v. 147, p. 295–314, https://doi.org/10.1016/j.solmat.2015.12.026.
- Luo, X., Wang, J., Dooner, M., and Clarke, J., 2015, Overview of current development in electrical energy storage technologies and the application potential in power system operation: Applied Energy, v. 137, p. 511–536, https://doi.org/10.1016/j.apenergy.2014.09.081.
- Mackay, D.A.R., and Simandl, G.J., 2014, Geology, market and supply chain of niobium and tantalum – a review: Mineralium Deposita, v. 49, p. 1025–1047, https://doi.org/10.1007/s00126-014-0551-2.
- Maldonado, S., 2020, The importance of new “sand-to-silicon” processes for the rapid future increase of photovoltaics: ACS Energy Letters, v. 5, p. 3623–3632, https://doi.org/10.1021/acsenergylett.0c02100.
- Marchal, J.C., Krug, D.J., McDonnell, P., Sun, K., and Laine, R.M., 2015, A low cost, low energy route to solar grade silicon from rice hull ash (RHA), a sustainable source: Green Chemistry, v. 17, p. 3931–3940, https://doi.org/10.1039/c5gc00622h.
- Mariano, A.N., and Mariano Jr., A., 2012, Rare earth mining and exploration in North America: Elements, v. 8, p. 369–376, https://doi.org/10.2113/gselements.8.5.369.
- Mendoza-Vizcaino, J., Raza, M., Sumper, A., Díaz-González, F., and Galceran-Arellano, S., 2019, Integral approach to energy planning and electric grid assessment in a renewable energy technology integration for a 50/50 target applied to a small island: Applied Energy, v. 233–234, p. 524–543, https://doi.org/10.1016/j.apenergy.2018.09.109.
- Merli, R., Preziosi, M., and Acampora, A., 2018, How do scholars approach the circular economy? A systematic literature review: Journal of Cleaner Production, v. 178, p. 703–722, https://doi.org/10.1016/j.jclepro.2017.12.112.
- Miao, Y., Hynan, P., von Jouanne, A., and Yokochi, A., 2019, Current Li–ion battery technologies in electric vehicles and opportunities for advancements: Energies, v. 12, 1074, https://doi.org/10.3390/en12061074.
- Millensifer, T.A., Sinclair, W.D., Jonasson, I.R., and Lipmann, A., 2014, Rhenium, in Gunn, G., ed., Critical Metals Handbook, Chapter 14: John Wiley and Sons Ltd., p. 340–360, https://doi.org/10.1002/9781118755341.ch14.
- Nagahata, R., Mori, Y., Saito, Y., Takeuchi, K., Shimizu, Y., Shimizu, M., and Benioub, R., 2021, Efficient carbothermal reduction of diatomaceous earth to silicon using microwave heating: Materials Chemistry and Physics, v. 257, 123744, https://doi.org/10.1016/j.matchemphys.2020.123744.
- Nassar, N.T., 2017, Shifts and trends in the global anthropogenic stocks and flows of tantalum: Resources, Conservation and Recycling, v. 125, p. 233–250, https://doi.org/10.1016/j.resconrec.2017.06.002.
- Oberbeck, L., Alvino, K., Goraya, B., and Jubault, M., 2020, IPVF’s PV technology vision for 2030: Progress in Photovoltaics Research and Applications, v. 28, p. 1207–1214, https://doi.org/10.1002/pip.3305.
- Olivetti, E.A., Ceder, G., Gaustad, G.G., and Fu, X., 2017, Lithium-ion battery supply chain considerations: analysis of potential bottlenecks in critical metals: Joule, v. 1, p. 229–243, https://doi.org/10.1016/j.joule.2017.08.019.
- Olson, J., 2021, Graphite (Natural): Mineral Commodity Summaries: United States Geological Survey, p. 72–73, https://pubs.usgs.gov/periodicals/mcs2021/mcs2021.pdf.
- Paradis, S., 2015, Indium, germanium and gallium in volcanic-and sediment-hosted base-metal sulphide deposits: Symposium on Strategic and Critical Materials Proceedings, November 13–14, 2015, Victoria, British Columbia: British Columbia Ministry of Energy and Mines, Geological Survey Paper, v. 3, p. 23–29.
- Pavel, C.C., Lacal-Arántegui, R., Marmier, A., Schüler, D., Tzimas, E., Buchert, M., Jenseit, W., and Blagoeva, D., 2017a, Substitution strategies for reducing the use of rare earths in wind turbines: Resources Policy, v. 52, p. 349–357, https://doi.org/10.1016/j.resourpol.2017.04.010.
- Pavel, C.C., Thiel, C., Degreif, S., Blagoeva, D., Buchert, M., Schüler, D., and Tzimas, E., 2017b, Role of substitution in mitigating the supply pressure of rare earths in electric road transport applications: Sustainable Materials and Technologies, v. 12, p. 62–72, https://doi.org/10.1016/j.susmat.2017.01.003.
- Polyak, D.E., 2021, Vanadium: Mineral Commodity Summaries: United States Geological Survey, p. 180–181, https://pubs.usgs.gov/periodicals/mcs2021/mcs2021.pdf.
- Richter, A., Hermle, M., and Glunz, S.W., 2013, Reassessment of the limiting efficiency for crystalline silicon solar cells: IEEE Journal of Photovoltaics, v. 3, p. 1184–1191, https://doi.org/10.1109/JPHOTOV.2013.2270351.
- Roberts, S., and Gunn, G., 2014, Cobalt, in Gunn, G., ed., Critical Metals Handbook, Chapter 6: John Wiley and Sons, p. 122–149, https://doi.org/10.1002/9781118755341.ch6.
- Roskill, 2018, Roskill: Neodymium prices surge as permanent magnet demand looks set to take off [Posted January 18]: PR Newswire, https://www.prnewswire.com/news-releases/roskill-neodymium-prices-surge-as-permanent-magnet-demand-looks-set-to-take-off-669905463.html.
- Roskill, 2019, Rare earths: Taiwan boosts its offshore wind energy capacity [Posted June 21]: Roskill, https://roskill.com/news/rare-earths-taiwan-boosts-its-offshore-wind-energy-capacity/. Accessed: June 21, 2020.
- Sánchez-Díez, E., Ventosa, E., Guarnieri, M., Trovò, A., Flox, C., Marcilla, R., Soavi, F., Mazur, P., Aranzabe, E., and Ferret, R., 2021, Redox flow batteries: Status and perspective towards sustainable stationary energy storage: Journal of Power Sources, v. 481, 228804, https://doi.org/10.1016/j.jpowsour.2020.228804.
- Sandia National Laboratories, 2020, U.S. Department of Energy Global Energy Storage Database, https://www.sandia.gov/ess-ssl/global-energy-storage-database-home/.
- Sapunkov, O., Pande, V., Khetan, A., Choomwattana, C., and Viswanathan, V., 2015, Quantifying the promise of ‘beyond’ Li–ion batteries: Translational Materials Research, v. 2, 045002, http://dx.doi.org/10.1088/2053-1613/2/4/045002.
- Schmidt, O., Melchior, S., Hawkes, A., and Staffel, I., 2019, Projecting the future levelized cost of electricity storage technologies: Joule, v. 3, p. 81–100, https://doi.org/10.1016/j.joule.2018.12.008.
- Schnebele, E.K., 2021, Manganese: Mineral Commodity Summaries: United States Geological Survey, p. 104–105, https://pubs.usgs.gov/periodicals/mcs2021/mcs2021.pdf. Accessed: May 15, 2021.
- Schulze, R., and Buchert, M., 2016, Estimates of global REE recycling potentials from NdFeB magnet material: Resources, Conservation and Recycling, v. 113, p. 12–27, https://doi.org/10.1016/j.resconrec.2016.05.004.
- Schwarz-Schampera, U., 2014, Indium, in Gunn, G., ed., Critical Metals Handbook, Chapter 9: John Wiley and Sons, p. 204–229, https://doi.org/10.1002/9781118755341.ch9.
- Shi, Y., Eze, C., Xiong, B., He, W., Zhang, H., Lim, T. M., Ukil, A., and Zhao, J., 2019, Recent development of membrane for vanadium redox flow battery applications: A review: Applied Energy, v. 238, p. 202–224. https://doi.org/10.1016/j.apenergy.2018.12.087.
- Simandl, G.J., 2014, Geology and market-dependent significance of rare earth element resources: Mineralium Deposita, v. 49, p. 889‒904, https://doi.org/10.1007/s00126-014-0546-z.
- Simandl, G.J., and Paradis, S., 2018, Carbonatites: Related ore deposits, resources, footprint, and exploration methods: Applied Earth Science, v. 127, p. 123‒152, https://doi.org/10.1080/25726838.2018.1516935.
- Simandl, G.J., Akam, C., and Paradis, S., 2015, Which materials are ‘critical’ and ‘strategic’, in Simandl, G.J., and Neetz, M., eds., Symposium on Strategic and Critical Materials Proceedings, November 13–14, 2015, Victoria, British Columbia: British Columbia Ministry of Energy and Mines, Geological Survey Paper 2015-3, p. 1–4.
- Simandl, G.J., Burt, R.O., Trueman, D.L., and Paradis, S., 2018, Economic Geology Models 4. Tantalum and Niobium: Deposits, resources, exploration methods and market-A primer for geoscientists: Geoscience Canada, v. 45, p. 85–96, https://doi.org/10.12789/geocanj.2018.45.135.
- Solar Energy Industries Association, 2018, Solar market insight report 2018 Q3: SEIA/Wood Mackenzie Power & Renewables, https://www.seia.org/research-resources/solar-market-insight-report-2018-q3.
- Swain, N., and Mishra, S., 2019, A review on the recovery and separation of rare earths and transition metals from secondary resources: Journal of Cleaner Production, v. 220, p. 884–898, https://doi.org/10.1016/j.jclepro.2019.02.094.
- U.S. Department of Defense, 2013, Strategic and critical materials 2013 report on stockpile requirements: Office of the Under Secretary of Defense for Acquisition, Technology and Logistics, 189 p., https://mineralsmakelife.org/assets/images/content/resources/Strategic_and_Critical_Materials_2013_Report_on_Stockpile_Requirements.pdf. Accessed: July 15, 2015.
- U.S. Department of Energy, 2011, Critical materials strategy: Office of Policy and International Affairs, 190 p., https://www.energy.gov/sites/prod/files/DOE_CMS2011_FINAL_Full.pdf.
- U.S. Department of the Interior, 2018, Final list of critical minerals 2018: Federal Register Document Number 2018-10667, v. 83, p. 23296–23297, https://www.govinfo.gov/content/pkg/FR-2018-05-18/pdf/2018-10667.pdf.
- U.S. Geological Survey, 2021, Mineral commodity summaries 2021: U.S. Geological Survey, 200 p., https://doi.org/10.3133/mcs2021.
- Vanýsek, P., and Novák, V., 2017, Redox flow batteries as the means for energy storage: Journal of Energy Storage, v. 13, p. 435–441, https://doi.org/10.1016/j.est.2017.07.028.
- Verbaan, N., Bradley, K., Brown, J., and Mackie, S., 2015, A review of hydrometallurgical flowsheets considered in current REE projects, in Simandl, G.J., and Neetz, M., eds., Symposium on Strategic and Critical Materials Proceedings, November 13–14, 2015, Victoria, British Columbia: British Columbia Ministry of Energy and Mines, Geological Survey Paper 2015-3, p. 147–162.
- Walker, M., 2018, Hype cycles for emerging technologies, 2018 [Posted August 6]: Gartner Incorporated, Document Number G00340159, https://www.gartner.com/en/documents/3885468/hype-cycle-for-emerging-technologies-2018.
- Watts, M., 2010, Shock & ore: The scramble for rare earth self-sufficiency: Industrial Minerals, v. 13, p. 35–41.
- Widmer, J.D., Martin, R., and Kimiabeigi, M., 2015, Electric vehicle traction motors without rare earth magnets: Sustainable Materials and Technologies, v. 3, p. 7–13, https://doi.org/10.1016/j.susmat.2015.02.001.
- World Bank Group, 2017, The growing role of minerals and metals for a low carbon future: World Bank Group, Washington, DC., 111 p., http://documents1.worldbank.org/curated/en/207371500386458722/pdf/117581-WP-P159838-PUBLIC-ClimateSmartMiningJuly.pdf. Accessed: May 15, 2021.
- Xakalashe, B.S., and Tangstad, M., 2011, Silicon processing: from quartz to crystalline silicon solar cells, in Jones, R.T., and den Hoen, P., eds., Southern African Pyrometallurgy 2011: South African Institute of Mining and Metallurgy, Johannesburg, 6–9 March 2011, p. 83–99.
- Zhou, Y., Li, J., Rechberger, H., Wang, G., Chen, S., Xing, W., and Li, P., 2020, Dynamic criticality of by-products used in thin-film photovoltaic technologies by 2050: Journal of Cleaner Production, v. 263, 121599, https://doi.org/10.1016/j.jclepro.2020.121599.