Bismuth. View of grains of bismuth, a chemical element. Bismuth is a silvery-white metal belonging to group V of the periodic table. The most important bismuth ores are bismuthinite or bismuth glance (bismuth sulphide) and bismite (bismuth oxide). Bismuth has extremely low thermal and electrical conductivities. It is used to make low melting point alloys and solders, and in casting alloys, which expand on solidification giving clear replication of intricate features. Bismuth has the chemical symbol Bi, an atomic number of 83 and an atomic weight of 208.98.