This bismuth crystal cluster is from Germany. Bismuth is a native, metal, element (Bi) whose crystals are rarely found in nature. The crystal form of the metal are uncommon and they are usually small in size. Impressive large crystals, like these, can however be grown under laboratory conditions using centrifugal processes. This cluster contains stacked and hoppered crystals.They have a brilliant iridescence and a mirror metallic luster. The back of the piece is flat and this is the centrifuge attachment point. This cluster measures 1 7/8 x 1 1/8 x 1 inches or 48 x 28 x 25 mm.