Iridium is a stable metal that chemically unreactive, like platinum and gold. Iridium is the most resistant to oxidation of all metals.
A very hard, brittle, silvery-white transition metal of the platinum group, iridium is generally credited with being the second densest element (after osmium) based on measured density, although calculations involving the space lattices of the elements show that iridium is denser. Iridium is a hard, brittle, lustrous, dense, transition metal of the platinum family. It is silvery-white and it is notable for being the most corrosion resistant element known. It is unaffected by air, water and acids. 1 The Element Iridium in Chemistry The element iridium is a platinum group metal that is a very durable, hard, and lustrous metal and is similar to platinum. Iridium is a metallic element with the atomic number 77 and the symbol Ir. On the periodic table of elements, it is found in Group 9, between platinum and osmium. It is referred to as a “transition metal” and also as a “platinum metal,” along with ruthenium, rhodium, palladium, osmium, and platinum itself. Making the world better, one answer at a time. Iridium is a stable metal that chemically unreactive, like platinum and gold. Iridium is the most resistant to oxidation of all metals. It can be used is as a hardening agent in alloys with Platinum and Osmium. Sometimes used in medical therapies e.g. treating prostate cancer by radiation therapy. Used for crucibles, special containers and other apparatus resistant to intense heat. Under one sky, the world is becoming Iridium connected in new and diversified markets, delivering high-value solutions that are expanding the boundaries of business interests. Pure iridium is very brittle and is nearly impossible to machine. It is primarily used as a hardening agent for platinum. Platinum-iridium alloys are used to make crucibles and other high temperature equipment. Iridium is also alloyed with osmium to make the tips of fountain pens and compass bearings.
https://en.wikipedia.org/wiki/Iridium http://www.lenntech.com/periodic/elements/ir.htm http://www.answers.com/Q/What_is_the_use_of_iridium http://www.wisegeek.com/what-is-iridium.htm http://www.answers.com/Q/What_is_the_use_of_iridium https://www.iridium.com/ http://education.jlab.org/itselemental/ele077.html
what is iridium