Indium - Information

Atomic Number: 49

Atomic Weight: 114.818(3)

Electronic Configuration: [Kr]5s²4d¹⁰5p¹

Appearance - Indium is a soft silvery white solid metal at 298K. It gives a high pitched 'cry' when the pure metal is bent.

Origin - Indium was named after the brilliant indigo line in its spectra.

History - discovered by Reich and Richter. Until 1924 only a gram of pure indium existed on the planet.

Sources - Canada is the main producer of indium (about 1 000 000 troy ounces p.a.).Indium is mainly produced from residues generated from zinc ore processing.

Uses -

• Indium is useful for making low melting alloys such as 24% indium/76% gallium (liquid at 298K).
• It wets glass like gallium.
• The first large-scale application of indium was as a coating for bearings in high-performance aircraft engines during World War II.
• The amount of indium consumed p.a. is pretty much a function of worldwide LCD production as this is its main use today.
• It can form a mirror with comparable properties to that as made with silver but without its susceptibiltiy to atmospheric corrosion when evaporated onto glass.

Handling and Costs - Some evidence suggests that indium may possess a low level of toxicity, obviously great care should be taken until further data is known. Depending on purity up to $188/Kg.