Iridium was discovered in 1804 by Smithson Tenant. Its name derives from the Latin word "iridis" which means "rainbow".
Iridium's melting point is at 2410.0 C (2683.15 K, 4370.0 F) and its boiling point is at 4527.0 C (4800.15 K, 8180.6 F).
Iridium is a hard, brittle, silver-white transition metal.
Iridium is the second densest element.
Iridium is the most corrosion resistant element.
Iridium has the 10th highest melting point among all chemical elements.
Iridium has the second highest modulus of elasticity (osmium has the highest).
Iridium is an expensive metal (more than $1000/oz).
Iridium dust is reactive and flammable.
Iridium is one of the rarest elements in Earth's crust.
Gold is 40 times more abundant than iridium.
Iridium is usually found in meteorites.
Iridium is found as an uncombined element or in natural alloys.
Iridium has two stable isotopes: 191-Ir and 193-Ir (the most abundant).
The largest reserves of iridium are in South Africa, Russia, and Canada.
Iridium is a byproduct of nickel and copper production.
Iridium is used for the following applications: compass bearings and balances production, aircraft engine parts, deep water pipes, hardening agent in platinum alloys, in computers memory, electrical contacts, as a source of gamma radiation in cancer treatment, in robotic spacecrafts, in X-ray optics, in the production of anti-protons, and other very niche applications.
Iridium in bulk form is not hazardous to human health but iridium powder is irritant and can ignite in the air.