A mineral consisting of calcium tungstate, CaWO₄. Scheelite occurs in colourless to white, tetragonal crystals (see illus.); it may also be massive and granular. Its fracture is uneven, and its lustre is vitreous to adamantine. Scheelite has a hardness of 4.5–5 on Mohs scale and a specific gravity of 6.1. Its streak is white. The mineral is transparent and fluoresces bright bluish-white under ultraviolet light.