Bismuth

Bismuth is a brittle, silvery metal in the post-transition metals, a group of metals that often melt more easily than many structural metals. It occurs both as a native metal and in ores, especially bismuthinite (a sulfide) and bismite (an oxide). Most bismuth is not mined on its own: it is recovered while refining lead and other metals, then separated from impurities to produce the metal. Bismuth expands as it freezes, unlike most metals, which makes it useful in some casting alloys. Its compounds—not the metal itself—are used in products such as cosmetics and the stomach medicine bismuth subsalicylate. The metal is also used in some alloys designed to replace lead.