Rare-earth ferrosilicon (RE-FeSi) is an alloy used in specialty steelmaking and foundry applications where rare-earth additions modify inclusion morphology and improve mechanical properties. Production is concentrated in integrated alloy plants in China and a smaller number of specialty alloy producers elsewhere. Market research shows a small but steadily growing global market value (hundreds of millions USD), with projections of mid-single digit CAGR into the late 2020s as specialty steel demand and higher performance alloying needs rise.