Main uses
Bismuth compounds account for about half the global production of bismuth. They are used in cosmetics; pigments; and a few pharmaceuticals, notably bismuth subsalicylate, used to treat diarrhea. Bismuths unusual propensity to expand as it solidifies is responsible for some of its uses, as in the casting of printing type. Bismuth has unusually low toxicity for a heavy metal. As the toxicity of lead and the cost of its environmental remediation became more apparent during the 20th century, suitable bismuth alloys have gained popularity as replacements for lead. Presently, around a third of global bismuth production is dedicated to needs formerly met by lead. History and etymology
Bismuth metal has been known since ancient times and it was one of the first 10 metals to have been discovered. The name bismuth dates to around 1665 and is of uncertain etymology. The name possibly comes from obsolete German Bismuth, Wismut, Wissmuth (early 16th century), perhaps related to Old High German hwiz ("white"). The New Latin bisemutium (coined by Georgius Agricola, who Latinized many German mining and technical words) is from the German Wismuth, itself perhaps from weiße Masse, meaning "white mass".The element was confused in early times with tin and lead because of its resemblance to those elements. Because bismuth has been known since ancient times, no one person is credited with its discovery. Agricola (1546) states that bismuth is a distinct metal in a family of metals including tin and lead.
Bismuth compounds (including sodium bismuth tartrate) were formerly used to treat syphilis. Arsenic combined with either bismuth or mercury was a mainstay of syphilis treatment from the 1920s until the advent of penicillin in 1943. "Milk of bismuth" (an aqueous suspension of bismuth hydroxide and bismuth subcarbonate) was marketed as an alimentary cure-all in the early 20th century, and has been used to treat gastrointestinal disorders. Bismuth subnitrate (Bi5O(OH)9(NO3)4) and bismuth subcarbonate (Bi2O2(CO3)) are also used in medicine. Cosmetics and pigments
Bismuth oxychloride (BiOCl) is sometimes used in cosmetics, as a pigment in paint for eye shadows, hair sprays and nail polishes. This compound is found as the mineral bismoclite and in crystal form contains layers of atoms (see figure above) that refract light chromatically, resulting in an iridescent appearance similar to nacre of pearl. It was used as a cosmetic in ancient Egypt and in many places since. Bismuth white (also "Spanish white") can refer to either bismuth oxychloride or bismuth oxynitrate (BiONO3), when used as a white pigment. Bismuth vanadate is used as a light-stable non-reactive paint pigment (particularly for artists paints), often as a replacement for the more toxic cadmium sulfide yellow and orange-yellow pigments. The most common variety in artists paints is a lemon yellow, visually indistinguishable from its cadmium-containing alternative. Metal and alloys
Bismuth is used in metal alloys with other metals such as iron. These alloys are used in automatic sprinkler systems for fires.