Mineral economics of the rare-earth elements

The mineral economics of rare-earth elements (REEs) are a crucial factor in the development of new REE mineral exploration and mining projects as well as being defining factors in the security of supply and the determination of the criticality (vulnerability to supply restriction for a variety of factors that can cause supply–demand imbalances) of this group of elements. Production and, more importantly, refining of REEs remains focused in China, leading to a national monopoly that could cause future supply constraints and price volatility. Variations in the demand for individual REEs are demonstrated by December 2020 prices that varied between ~ USD$1.8/kg for samarium (Sm) oxides and ~ USD$2.15/kg for cerium (Ce) oxides to ~ $1305/kg for terbium (Tb) metal, reflecting lower supply and higher demand for Tb relative to Sm and Ce. Price variations between individual REEs are far greater than short-term fluctuations in the prices of an individual REE product. The higher prices for certain REEs, such as neodymium (Nd), dysprosium (Dy), and Tb, create further issues when compared with primary REE supply from orebodies, which is typically dominated by Lanthanum (La), Ce, and the other light REEs (LREEs). This balance problem is just one aspect of the lack of security of supply of REEs, with others including the small size and limited transformational growth potential of the sector relative to other parts of the minerals industry, volatile REE prices, and the geographical distribution of REE mining and (especially) processing and refining. These factors mean that long-term planning in this sector is difficult, especially relative to the ~ 10–20 years needed to bring a mineral exploration project into production. The range of problems affecting REE supply, including securing further domestic supplies within countries that either do not or only have limited current REE extraction or development of secondary resources of these elements, strongly suggests that policymaking and associated geopolitical approaches to secure imports of REEs will be vital tools in reducing the REE criticality and security of supply issues that face many countries who rely on secure access to primary REE supply. Global mineral and metal production from 1956 to 2018 normalized to 1956 production (a) and in per capita terms normalized to 1956 production (b) showing the increase in global mineral and metal use per head of population with dashed lines indicate elements with lower normalized production in 2021 than in 1956. These diagrams effectively demonstrate the increase in the mineral and metal requirements for modern life, especially given the increase in recycling of a significant proportion of these commodities over the same period. The increase in demand for rare-earth elements (REEs) is especially visible, with modern society using ~ 12 times more REE per person in 2018 compared to 1956 and with primary REE production from mining some ~ 32 times higher in 2018 compared to 1956.