Iridium is a silvery-white shining precious metal from the platinum metals group. It is rated as the most corrosion-resistant element at all. Due to its hardness and brittleness, it can be mechanically processed only with difficulty.
Iridium is often used in alloys; especially with platinum. It makes the alloys harder and more resistant to corrosions. Platinum-iridium alloys are, for example, produced for the chemical industry, the space technology and spark plug electrodes. Due to its excellent biocompatibility, there are diverse platinum- iridium products for the medical technology. It acts as a special UV protection on high-quality sunglasses. Iridium catalysts are applied in satellite and rocket engines. It is also used for the anode coating in the chlorine-alkaline electrolysis.