19 Facts About Indium

Indium is a chemical element with the symbol In and atomic number 49.

Indium has a melting point higher than sodium and gallium, but lower than lithium and tin.

Indium was discovered in 1863 by Ferdinand Reich and Hieronymous Theodor Richter by spectroscopic methods.

Indium is a minor component in zinc sulfide ores and is produced as a byproduct of zinc refinement.

Indium is a silvery-white, highly ductile post-transition metal with a bright luster.

Indium has greater solubility in liquid mercury than any other metal .

Indium is rather basic in aqueous solution, showing only slight amphoteric characteristics, and unlike its lighter homologs aluminium and gallium, it is insoluble in aqueous alkaline solutions.

Indium has 39 known isotopes, ranging in mass number from 97 to 135.

Indium is one of three known elements of which the stable isotope is less abundant in nature than the long-lived primordial radioisotopes.

Indium is the 68th most abundant element in Earth's crust at approximately 50 ppb.

Indium is produced exclusively as a by-product during the processing of the ores of other metals.

Indium is used in photovoltaics as the semiconductor copper indium gallium selenide, called CIGS solar cells, a type of second-generation thin-film solar cell.

Indium is used in PNP bipolar junction transistors with germanium: when soldered at low temperature, indium does not stress the germanium.

Indium wire is used as a vacuum seal and a thermal conductor in cryogenics and ultra-high-vacuum applications, in such manufacturing applications as gaskets that deform to fill gaps.

Indium is an ingredient in the gallium–indium–tin alloy galinstan, which is liquid at room temperature and replaces mercury in some thermometers.

Indium is one of many substitutes for mercury in alkaline batteries to prevent the zinc from corroding and releasing hydrogen gas.

Indium is added to some dental amalgam alloys to decrease the surface tension of the mercury and allow for less mercury and easier amalgamation.

Indium compounds are mostly not absorbed upon ingestion and are only moderately absorbed on inhalation; they tend to be stored temporarily in the muscles, skin, and bones before being excreted, and the biological half-life of indium is about two weeks in humans.

Indium lung is a lung disease characterized by pulmonary alveolar proteinosis and pulmonary fibrosis, first described by Japanese researchers in 2003.