Bismuth is indicated on the periodic table with symbol Bi, atomic number 83, and atomic mass of 208.98. Bismuth is a brittle, crystalline, white metal with a slight pink tinge. It has a variety of uses, including cosmetics, alloys, fire extinguishers and ammunition. It is probably best known as the main ingredient in stomachache remedies such as Pepto-Bismol. Bismuth, element 83 on the periodic table of elements, is a post-transition metal, according to Los Alamos National Laboratory. (Different versions of the periodic table represent it as a transition metal.) Transition metals — the largest group of elements, which includes copper, lead, iron, zinc and gold — are very hard, with high melting points and boiling points. Post-transition metals share some characteristics of transition metals but are softer and conduct more poorly. In fact, bismuth's electric and thermal conductivity is unusually low for a metal. It also has a particularly low melting point, which enables it to form alloys that can be used for molds, fire detectors and fire extinguishers. Bismuth metal is used in the manufacture of low melting solders and fusible alloys as well as low toxicity bird shot and fishing sinkers. Certain bismuth compounds are also manufactured and used as pharmaceuticals. Industry makes use of bismuth compounds as catalysts in manufacturing acrylonitrile, the starting material for synthetic fibers and rubbers. Bismuth is sometimes used in the production of shot and shotguns.