Iridium is a very hard, brittle, silvery-white transition metal of the platinum group, and is generally credited with being the second densest element (after osmium). It is also the most corrosion-resistant metal, and it’s 40 times rarer than gold.
Iridium – The MOST RARE Metal on Earth!
In much higher concentrations, iridium is found in meteorites and also in the depths of the Earth, in magma. Iridium, in addition to its rarity is even the most stable metal that does not oxidize in air up to 2000 degrees, and is not soluble in either acid or aqua regia.
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