All About Indium – Precious Metal Series

Indium is a lustrous, malleable, soft and ductile metal. It is silver white in color and has a tetragonal structure that is face-centered. Over a broad range of temperatures, indium is liquid, just like its group mate, gallium. Both gallium and indium are able to wet glass. In the air and in water, indium remains stable. However, in acids, it dissolves. Indium ignites when heated above its melting point and a violent flame is created.

Not Widely Dispersed

In the environment, indium is not exactly dispersed widely. Soils that are cultivated are reported to have a richer indium content compared to sites that are not cultivated. In the industry, indium is the by-product of smelting lead and zinc sulfide ores. In Russia, specimens of indium uncombined metal have been found. In Siberia, indite, an indium mineral has been found as well, but rarely. Production of Indium in the world comes from Canada, mainly with about seventy-five annual tonnes. The metal reserves are estimated to be more than one thousand five hundred tonnes.

Uses of Indium

Indium is utilized in fusible allows that are low-melting. It is used as a protective plate for metal surfaces such as bearings. It can be utilized to form a mirror surface resistant to corrosion. When allowed to deposit on glass and evaporated, it produces a mirror with the same great quality as silver. Foils of indium are used for assessing what is happening inside nuclear reactors. Also, indium is used in sodium vapor lamps as a light filter.

Also, Indium is exclusively produced during the time when other metal ores are processed. The main material sources are ores of sulfidic zinc, which sphalerite mostly hosts. There are also most likely minor amounts extracted from ores of sulfidic copper. During zinc smelting’s electrowinning process, indium accumulates in the residues rich in iron. From that point, there are different ways to extract it. It can also be directly recovered from the processed solutions. Electrolysis further purifies indium. The process varies with every smelter mode of operation.

The status indium has as a by-product indicates that the production is constrained by the amount of comer and sulfidic zinc ores extracted every year. Thus, in terms of supply potential, its availability needs to be discussed. At the moment China is indium’s leading producer with its 2016 production of 290 tonnes. South Korea comes next and then at 70 tonnes, Japan. In fourth place is Canada with 65 tonnes. LCD production is the reason for the main consumption of indium. There was a rapid rise in demand from the late nineties to 2010 with the LCD computer monitor becoming very popular as well as TV sets which account for half of the consumption of indium. Particularly in Japan, the increased efficiency of manufacturing maintains a balance between supply and demand. Keep in mind that there is a less than one per cent recycling rate for the end-of-life of Indium, however.