Yttrium is a silvery-metallic element (atomic number 39) used in many advanced technological applications. Due to its unique thermal and electrical properties, it plays a role in modern electronics and specialized materials. Yttrium is used in high-performance alloys to increase strength and heat resistance, and in phosphors for white light-emitting diodes (LEDs) and display screens. Compounds like Yttrium Aluminum Garnet (YAG) are used in high-power lasers, and the radioisotope Yttrium-90 is utilized in targeted cancer therapies. The geological sources and extraction methods of this element are of economic and strategic interest.
Yttrium’s Geological Association and Mineral Hosts
Yttrium does not exist as a free element but is always found chemically bound within mineral structures. It is chemically similar to the lanthanide series, categorized as a heavy Rare Earth Element (REE). This similarity means Yttrium is often concentrated in the same geological deposits as elements like Dysprosium and Terbium.
Yttrium is primarily sourced from specific mineral hosts, notably the phosphate mineral Xenotime, which contains a high percentage of Yttrium phosphate. Another source is Monazite, a reddish-brown phosphate mineral that is richer in light REEs but still yields recoverable Yttrium. These minerals are concentrated in placer deposits, such as heavy-mineral beach sands, or found in hard rock formations like pegmatites and carbonatites.
A major source, especially in Asia, is the ion-adsorption clay deposit. In these weathered clay ores, Yttrium and other REEs are loosely held onto clay particles, simplifying initial extraction compared to hard rock mining. Yttrium is rarely mined as a primary target; it is usually recovered as a co-product during the extraction of other REEs, uranium, or heavy minerals.
Leading Global Producers and Major Reserves
Yttrium production is highly concentrated, with a few nations dominating the global supply. Global mine production of Yttrium contained within rare-earth mineral concentrates is estimated to range between 10,000 and 15,000 tons per year. The majority of this production is controlled by China and Myanmar.
China maintains a dominant position, sourcing most of its supply from weathered clay ion-adsorption deposits in southern provinces like Guangdong and Jiangxi. These clay deposits are the main global source of heavy REEs, including Yttrium. Myanmar has emerged as a significant producer from similar clay deposits, contributing substantially to the world’s supply outside of China.
While global reserves of Yttrium are not precisely quantified, countries with substantial Rare Earth Oxide (REO) reserves indicate where future supply may originate. Countries holding REO reserves that contain Yttrium include Australia, Brazil, Russia, and Vietnam. Australia is developing projects targeting heavy REEs, positioning it as a potential major supplier. The distinction between reserves and current production is important, as some countries hold large reserves but lack the current mining and processing capacity, leading to dependency on major producers.
Processing Yttrium from Ore
After Yttrium-bearing ore is mined, it undergoes industrial processes to be rendered into a pure, usable form. The initial step is beneficiation, where the ore is crushed and milled to reduce particle size. This is followed by physical separation techniques, such as flotation or gravity separation, to create a mineral concentrate.
The next stage is hydrometallurgy, which uses aqueous solutions to extract the metal. The concentrate is subjected to chemical leaching, often involving strong acids like sulfuric or nitric acid, to dissolve the Yttrium and other rare earths into a liquid solution. This acid digestion breaks the chemical bonds within the mineral structure.
The final and most challenging step is the separation and purification of Yttrium from the other dissolved elements. Because all REEs have extremely similar chemical properties, this separation is a multi-stage and costly process. It is primarily achieved through solvent extraction, which selectively separates the individual rare earth ions based on small differences in their chemical behavior. The resulting Yttrium compound, usually an oxide, is then converted into metal or other compounds for technological use.