wolframite

Wolframite, (Fe,Mn)WO₄, is an iron manganese tungstate mineral that is the intermediate between ferberite (Fe²⁺ rich) and hübnerite (Mn²⁺ rich). Along with scheelite, the wolframite series are the most important tungsten ore minerals. Wolframite is found in quartz veins and pegmatites associated with granitic intrusives. Associated minerals include cassiterite, scheelite, bismuth, quartz, pyrite, galena, sphalerite, and arsenopyrite.