Diamonds are a hard crystalline form of carbon. These uncut diamonds are from the Russian State Precious Metals and Gemstones Collection Fund, part of the Russian Finance Ministry. Photographed in Moscow, in March
Unique crystal of small green Apatite (analyses indicated Fluorapatite) on two faces of a complete, well terminated Tanzanite crystal. I have seen Tanzanite spcimens with Apatite on the Graphite matrix, but never one with Apatite on the Tanzanite crystal.