|Producer||Principal applications||Product Form||Packaging|
|Trace elements max (Pt, Pd, Rh, Ru, Os)||0.010||0.020||0.045|
|Loss on ignition||0.01||0.01||0.01|
|Latin name||Iridium (Ir)|
|Group in Mendeleev's periodic table||VIII|
|Atomic weight||192.22, a platinum group metal|
|Melting point||t 2,447 °С|
Iridium is a platinum group metal. In 1804, the British chemist, Smithson Tennant, examined a black powder which was left after dissolving virgin platinum in aqua regia, and found that it contained two new elements. The salts of one of these new elements were coloured, quite literally, with all the colours of the rainbow. Tennant did not think too long about what to call his discovery, choosing the name “iridium”, from the Greek “iris”, or “rainbow”.
The world is not rich in this metal, with reserves in the ground not exceeding millionths of a per cent of the earth’s geological make-up. Each year, not more than a single ton of this metal is produced world-wide.