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
The Guinness Book of World Records names Painite as the rarest gem mineral on earth. Painite has so far only been found in Myanmar, Indonesia. Painite colors vary from pink to brown. Painite will appear a different color when viewed from different angles.