Holmium is a minor heavy rare earth element whose commercial importance is concentrated in a single dominant application: Ho:YAG (holmium-doped yttrium aluminum garnet) solid-state lasers operating at 2.09 μm. This wavelength is strongly absorbed by biological water, enabling Ho:YAG systems to achieve precise tissue ablation with limited thermal damage — making them the preferred tool for urological lithotripsy (laser ablation of kidney and bladder stones), prostate surgery (HoLEP), and a range of soft-tissue surgical procedures. Ho:YAG laser systems from manufacturers including Lumenis and Olympus represent the primary commercial demand for holmium oxide, and medical device supply chains are therefore the main interface between holmium's geological reality and its economic relevance.

Global Ho production is estimated at ~585 tonnes Ho₂O₃ equivalent in 2024 (derived from the USGS-reported 390,000 t world REE total at a ~0.15% basket share), with China supplying ~69% of mine output at aggregate REO shares — but a meaningfully higher actual share when deposit-type correction is applied, since Ho is enriched in China's southern ion adsorption clay deposits (~0.2–0.5% Ho₂O₃) rather than in LREE-dominant bastnaesite. China controls approximately 92% of global heavy REE separation capacity including Ho₂O₃ production. Burma's ion adsorption clay operations, before their 28% output decline in 2024, were a significant secondary Ho source due to the same HREE-enriched deposit character.

Unlike dysprosium or terbium, holmium was not directly targeted in China's April 2025 heavy REE export control measures (which named Sm, Gd, Tb, Dy, Lu, Sc, and Y). However, the structural supply chain reality is identical: near-total dependence on Chinese separation capacity for a material with no short-term domestic substitute production in the United States or Europe. Thulium fiber lasers at 1.9 μm are emerging as partial substitutes in some urological applications, but Ho:YAG remains the gold standard for high-energy stone ablation and broader surgical use. The path to supply chain resilience for Ho:YAG medical devices requires non-Chinese Ho₂O₃ separation capacity — a gap not yet addressed by current diversification investments that focus primarily on NdPr and HREE magnets.