Dims: 3.3 x 2.6 x 1.4" (8.4 x 6.6 x 3.6 cm)
Wt: 6.1 oz. (171.8 g)
Pingwu, Sichuan Province, China
Several black Cassiterite crystals rest on the muscovite base of this hand specimen. Most are intergrown into confusing clusters, but a few are separate and individual. The largest crystal has visible dimensions of 1.0 x 0.6 x 0.5" (2.5 x 1.5 x 1.3 cm), but is very warped, so that I am not really sure that it is even a single crystal! The other intergrown Cassiterites are also like this, though two of the largest show noticeable twinning. They do show definite crystalline faces, however, that are well-defined and possess a bright subadamantine luster. Their color is essentially black, though under a bright halogen light, one might see small glints of brown color near their edges. The base consists of a thick layer of small intergrown muscovite "books" that rest on a mica-schist base; there are a few small goshenite beryl crystals present in one area, but I think that most of these are incomplete.