The mineral Bismuth is a chemical element of symbol Bi and atomic number 83. It is a post-transition metal (pentavalent), chemically bearing a resemblance to Antimony and Arsenic. Bismuth, as an element, occurs in nature, even though for commercial purposes it is in the form of oxides and sulfides. As a free element its density is 86% like that of lead. A newly produced metal is silvery white in color and brittle. However, when exposed to the atmosphere, its color has a pink hue, on account of the oxidation on its surface. Among metals, Bismuth has the least thermal conductivity and it is the element with the highest diamagnetic element that occurs naturally.
Chemical Formula/symbol and atomic number
Symbol Bi and atomic number 83
Derivation Of Name
The metal Bismuth has been revealed since ages. Still, till the 18th century there was a frequent confusion about this metal with Tin and Lead, which had some similar physical properties. Even though its etymology (words origin) is not defined, there are chances that it is from the Arabic biismid, which means it has the property of antimony, and alternatively, comes from the German words wismuth (“White mass”) or wise masses that was translated into Latin as bisemutum in the middle of the sixteenth century.
In nature the element Bismuth often occurs in the brittle state having a white color of silver to a pink hue, with a discolor of iridescent oxide, exhibiting several colors ranging from blue to yellow. The inside border of this metal has a lower growth rate when compared to that of the outer border. As such, its structure resembles that of a staircase spiral. The oxide layer formed on the surface of the crystal is not of even thickness, thus the wavelengths of the light cause interference when reflected, leading to the display of rainbow colors. When Bismuth is burnt in air, a blue flame emanates from it and the oxide forms fumes of yellow.
Bismuth is used by certain manufacturers as an alternate measure for the transfer of potable water, such as valves for the purpose of exemption of lead, which is made compulsory in the United States This system is applied on a large scale to all commercial constructions and residential buildings. In the beginning of 1990s, researchers started conducting studies on Bismuth to assess its nontoxic properties as an alternative for lead in several applications.
In accordance with the Geological Survey conducted in the United States, the world’s production of Bismuth in the mines, in the year 2010 accounted for 8,900 tonnes, of which the greatest contribution was from China (with 6,500 tonnes), Mexico (850 tonnes) and Peru (1,100 tonnes). The production from the refinery was 16,000 tonnes, with China;s production at 13,000 tonnes, Belgium’s 800 tonnes and Mexico’s at 850 tonnes.
Half the production of Bismuth goes for the compounds of Bismuth. Bismuth compounds are used in the fields of pigments, cosmetics and in some pharmaceuticals, specially Pepto-bismuth. The unusually inclination of Bismuth to expand on freezing is responsible for a certain use, like casting printing types. As a heavy metal, the toxicity of Bismuth is low. The increased use of Bismuth alloys is because; recently the toxic property of lead has become more evident (At present it is one third of the production of Bismuth) and Bismuth is now an alternative of lead.