Dims: 2.7" x 2.0" x 1.9"(6.9 x 5.1 x 4.8)
Wt: 5.22 oz.(148.1 g)
Musonoie Mine, Kolwezi, Zaire
It is difficult to determine what the host rock is on this specimen- I would guess a hard shale or fine-grained sandstone. I do know, however, that at least 30% of its surface area is covered with a crust of tightly-packed Torbernite crystals. These crystals occur as thin, square-shaped tabular blades and are tightly intergrown. Their color is a uniform dark green, they have a pearly luster, and individual crystals are transparent. There is heavy damage- over 50% of the blades are broken. There is a lot of material on this crust, and veins of Torbernite, and possibly some malachite, permeate the host rock. I am guessing that the copper minerals in this specimen make up over half its weight.