Bismuth has been known since ancient times, and its name is derived from the German word Bisemutum. In the late Middle Ages, it was used in alloys and was often mentioned in alchemical writings as a symbol for purity. Bismuth is a brittle metal with a white, silver-pink hue and, when freshly formed, a glittering crystalline texture resembling silver. It is considered stable and, like lead and tin, does not corrode unless heated to very high temperatures.
Bismuth is an element found naturally in the earths crust, the fifth most abundant element in the crust. It occurs as an oxide, and its primary sources are bismuthinite, a sulfide ore, and bismite, an oxide ore. Its main use for hundreds of years has been in the production of lead, but today it has many additional applications. Bismuth is widely used in electronics and computer components, medical instruments and devices, fire detectors and extinguishers, and cosmetics.
Bismuth is also a Metalloid, which is an element able to form both metallic and non-metallic compounds, and due to its capability to form such a range of compounds, bismuth has a variety of uses. It is used to control viscosity in paints and other coatings, as an activator in catalysts, and in nuclear reactor fuels. Refined bismuth is also used in wire and cable insulation, plastic coatings and semiconductors, as well as being alloyed with lead and tin to form solder.
It is also used in alloys to improve strength, toughness and plasticity, with particularly advantageous properties for low-cost alloys for precision engineering, such as for gears and cams. Bismuth is also useful in alloying with metals such as cobalt, lead and tin for producing components for nuclear construction and for the casing of special nuclear fuels.
Bismuth is also found in many medicines and some dietary supplements. It is used as an antacid and to treat diarrhea, stomach ulcers, and other digestive problems. It can also be used to reduce the amount of gas in the intestinal tract and to stimulate the production of saliva and gastric secretions.
Bismuth has many chemical properties, including low chemical reactivity, low electrical conductivity and low melting point. It also has a high atomic number and a relatively low density, making it valuable for use in solid rocket propellant, radiation shielding and nuclear reactor fuels.
Bismuth is considered a non-toxic element, and its toxicity is significantly lower than that of lead, arsenic and mercury. It does not interact with other elements and is insoluble in water. The greatest risk of exposure is associated with its inhalation or ingestion in concentrations high enough to cause mental confusion and other neurological symptoms. However, since it occurs naturally in the environment, scientists have been able to determine appropriate safe levels of exposure.
In its pure form, bismuth has a wide range of uses. It is valued by manufacturers for its low melting point and relatively low density, which allow it to be cast into intricate shapes. Its low electrical conductivity and low reactivity also make it a good choice for applications such as fire detectors, extinguishers, and semiconductors, as well as for acidity control in paints and plastics. Additionally, its corrosion-resistance makes it an ideal choice for alloys used in electrical components.
