Dims: 2.6 x 2.2 x 1.0" (6.6 x 5.6 x 2.5 cm)
Wt: 4.23 oz. (119.9 g)
Reynolds County, Missouri, U.S.A.
I received this specimen with documentation that claimed it was a marcasite specimen, and indeed the reniform formations that comprise it are coated with both massive and crystalline marcaiste. However, upon turning the piece over, I saw that the marcasite makes up only a thin coating over the reniform Chalcopyrite. The specimen is generally in very good condition, showing very little fresh damage. The Chalcopyrite is only visible on the main breakage area that serves as the underside of the specimen, and has the classic deep golden coloration and metallic luster of its species. The marcasite that coats it has an almost blue-green coloration and a slightly duller metallic luster. The crystalline material has good orthorhombic form, though crystals are rounded and somewhat intergrown. The material on which these minerals rest is made up of a gray dolomitic limestone that contains several small, white dolomite crystals, most of which are broken.