This study compares characteristics and implications for sustainable resource management of supergene and primary mineral deposits. Supergene deposits, formed through weathering and oxidation near the Earth’s surface, represent a significant source of critical and industrial metals. The increasing demand and rising prices for these materials have heightened interest in supergene deposits due to their potential for low-cost production. Supergene deposits are superficial, have lower stripping ratios, and exhibit greater rock friability, potentially requiring less investment while providing substantial returns, even considering their relatively low grades. These characteristics lead to reduced energy consumption, smaller carbon footprints, and fewer acid and solubilizing compounds due to the absence of sulfides. However, processing supergene ore can require significant freshwater resources, especially for clay-rich ores that consume larger amounts of non-recoverable water and large surface footprints relevant to local communities and land rehabilitation. Most supergene deposits are in emerging countries, where mining practices are crucial for development. Some commodities, such as gold and cobalt in supergene deposits, attract artisanal and small-scale miners, often presenting challenges to ensure worker safety and abolish child labor. The global production of critical minerals faces market tensions due to monopolies, limited economic deposits worldwide, and trade restrictions, compromising supply security. The discovery and characterization of new deposits, to diversify supply sources, are essential to mitigate market concentration risks and enhance supply chain resilience, contributing to overall market stability. We demonstrate the importance of reviewing supergene ore deposit models with the Environment, Social, and Governance (ESG) lens to establish foundations for informed decision-making, and sustainable and responsible extraction and processing.
In recent years, the increasing demand of clean energy due to the energy transition has made it necessary to search for a reliable supply of most of the key minerals needed for the fulfilment of this demand. This has resulted in an increase of awareness on the impact a disruption in the supply chain or an excessive rise in price could cause. Thus, there is a need to understand this situation from a supply failure risk angle. Risk identification, the cause and effect of the supply failure, and its assessment have led to a fault-tree analysis. This analysis has shed light on cobalt as one of the highest at risk metals in terms of the impact and final probability calculated over the supply chain disruption. The obtained ALARP (“As Low As Reasonably Practicable”) shows a risk tolerable region which is still being discussed regarding the “inhabitable” region in case of a disruption of cobalt supply.
Mining in Europe is regulated by national mining, environmental and labor and other laws. Additionally, there are also general frameworks within which a mine operates or can operate in Europe: the challenges of sustainable development, the 2030 Agenda for Sustainable Development with its 17 Sustainable Development Goals, the challenges of an operation under the ESG guidelines (environmental, social and governance), and the recently enacted Critical Raw Materials Act of the EU with the target to produce 10% of the 17 defined strategic raw materials or raw material specifications within the EU by 2030. There is hardly a region in Europe where a newly planned mine does not encounter civil resistance. The reasons may be based on facts, but often they are emotional. Today, mining in Europe has to address mainly three issues: 1.) constraining the impact of the mining footprint to a minimum, 2.) enhancing the efficiency of the extraction of mineral commodities, 3.) trying to exploit and market everything along the entire mining process, including waste materials, water derived from the mine, thermal energy from the mine, and the underground space for other uses, e.g. storage. Two mines in Europe, which can be considered role models, are described: the tungsten mine Mittersill in Austria and the fluorite-barite mine Wolfach in the Black Forest in Germany.
Spain has several indications of rare earth deposits, often presented in the non-specialized media as potential reserves that could meet part of European demand. Most of these occurrences cannot be considered technically and economically viable due to the limited information available and their insufficient level of evaluation in certain categories. Rare earth elements (REE) have recently garnered significant attention as a strategic material for Europe and Spain. Therefore, in addition to the geological conditions of the deposits, their technical and economic viability for exploitation is being evaluated. This work proposes methods for analyzing mineral deposits in Spain, based on two internationally recognized systems for the classification and reporting of solid mineral reserves and resources: the CRIRSCO family of reporting standards and the United Nations Framework Classification (UNFC).
In the world of mineral raw materials of primary interest, such as fundamental minerals and metals, this monographic editorial issue addresses the supply chain of cutting-edge technologies, often affected by geopolitical challenges and limited geological information. The contributions received are grouped around natural reserves and their determination under current quality criteria, technology and supply economics, applied sustainability, and risk and geopolitical analysis.
