Garnet is any of several common, widespread aluminum or calcium silicate minerals occurring in two internally isomorphic series, generally crystallized. They are often embedded in igneous and metamorphic rocks and used both as gemstones and abrasives. Garnets are a group of common silicate minerals that have similar crystal structures and chemical compositions. It derives its name from ancient Greeks as color reminded them of the pomegranate seed or granatum. It is renowned ancient gem, treasured for thousands years. Garnets are actually one of the largest families of gemstones.