Siderite and Sphalerite Epimorphs after Calcite

Item Description

A dramatic and showy LARGE CABINET specimen from a small find that was brought out at Munich in 2006. These very unusual, barrel-shaped crystals are actually epimorphs, i. e. casts after Calcite crystals, which have been dissolved away. Microprobe analysis in South Africa by Bruce Cairncross and others shows that the shimmering, metallic-like coating is a mixture of Siderite and Sphalerite. The piece is very light weight for its size and, in fact, the casts are hollow, as the couple broken crystals on the specimen reveal. The striking cluster at the top really jumps out at you. The large crystal is 4.2 cm. The large crystal near the bottom is also 4.2 cm,. but it is also cracked. The top crystal is miraculously pristine. Interesting material from this unique find!