Cerium Oxide (glass polishing compound)

China's largest rare earth company by production volume; controls the Bayan Obo mining complex in Inner Mongolia — the world's largest rare earth deposit (light rare earths, primarily bastnäsite/monazite). Listed on Shanghai Stock Exchange. Subsidiary of Baotou Steel Group (itself a subsidiary of China Baowu, the world's largest steel company). Bayan Obo was initially developed as an iron ore deposit; rare earths were a 'byproduct' discovery that became the dominant geopolitical asset. China Northern's production plus other Chinese producers gives China ~60% of global ore production and ~85% of separated NdPr oxide.

Australian rare earth mining and processing company (ASX: LYC, HQ Kuala Lumpur/Perth); world's largest rare earth producer outside China. Mines at Mount Weld, Western Australia (one of the world's highest-grade rare earth deposits) and processes at LAMP (Lynas Advanced Materials Plant) in Kuantan, Malaysia. Produces separated rare earth oxides including lanthanum oxide, LREE carbonate, neodymium-praseodymium oxide. Lanthanum from Lynas is a byproduct of Nd/Pr production — lanthanum has limited premium uses and Lynas has at times struggled to find buyers for its lanthanum output. Lynas is also building a heavy rare earth processing facility in Kalgoorlie, Australia and an NdPr separation facility in Seadrift, Texas (DoD-funded) to establish non-China rare earth processing.

Belgian specialty chemicals company (Euronext: SOLB); produces CEROX® and OPALINE® brand cerium oxide polishing powders at La Rochelle, France via Rhodia subsidiary (acquired 2011, €3.4B). Product lines: CEROX® 1650, CEROX® 2610, SUPER CEROX® 1663, OPALINE® POLISSAGE — each optimized for specific glass/optics polishing applications. La Rochelle is one of the few Western-world facilities capable of producing polishing-grade CeO₂ (>99.9% purity, controlled particle size distribution) outside China. Same Solvay that invented synthetic soda ash (1861) and makes EUV photomask blanks via subsidiary AGC — now also the primary European source of glass polishing compound.

Operator of Mountain Pass, California — the only US rare earth mine and the largest rare earth mine outside of China. Produces rare earth concentrate (bastnasite ore) with ~15% of global rare earth ore production. As of 2024, still shipping concentrate to China (Shenghe Resources, a major MP investor) for separation into NdPr oxide. On-site solvent extraction (SX) separation plant being commissioned at Mountain Pass to enable US-based separation. MP Materials also building a rare earth magnet manufacturing facility in Fort Worth, Texas. Mountain Pass was the world's dominant rare earth mine until Chinese competition drove Molycorp (predecessor) bankrupt in 2015.

Japanese electronics materials company (merged with Hitachi Chemical 2020 to form Showa Denko Materials, rebranded as KH Neochem/Resonac 2023); produces cerium-based polishing powders for electrical equipment and semiconductor applications. Announced ¥500 million investment to expand cerium polishing powder capacity (targeted at precision glass, display panels, semiconductor substrates). Part of Japan's advanced materials sector; same company produces semiconductor CMP slurries and electronic chemicals.