The Geology of Tungsten: Granite-Related Veins and Skarns
Tungsten concentrates in deposits formed at the margins of cooling granite intrusions, the same kind of setting that produces tin, covered on tin's page.
Tungsten, like tin covered on its own geology page, concentrates specifically at the margins of cooling granite intrusions, where late-stage, metal-rich fluids deposit it in veins and, in a genuinely distinct setting, in skarns, where those fluids reacted with surrounding limestone.
Wolframite and scheelite, the two main ore minerals
Wolframite (iron-manganese tungstate) forms in granite-related veins, the same setting tin’s cassiterite often occurs in, which is why the two metals are frequently found together in the same deposits. Scheelite (calcium tungstate) forms more commonly in skarns, the limestone-reaction deposits described above, a genuinely different mineralogical and geological pathway to the same element.
Why tungsten and tin so often travel together geologically
Because both elements concentrate in the same late-stage granite fluids, many of the deposits covered on tin’s geology page also carry meaningful tungsten, a real geological coupling, not a coincidence, that shows up directly in how several countries (China, Bolivia) appear as significant producers of both metals.
Sources: deposit-type framing draws on standard economic geology references (USGS Mineral Commodity Summaries); production figures reference the production data elsewhere on this site.