Definition

Osmium is a chemical component that has the symbol Os. Osmium is a solid, brittle, blue-gray or blue-black transition metal in the platinum family, and is the densest natural element. Osmium is establish in nature as an alloy, frequently in platinum ores. Osmium is also used in alloys, with platinum, iridium and other platinum group metals. Those alloys are employed in fountain pen tips, electrical contacts and in other applications where extreme durability and hardness are needed.

Properties

Osmium is an enormously dense, blue-gray, hard but brittle metal that remains shiny even at high temperatures. Due to its hardness, brittleness, and very high melting point solid osmium is difficult to machine, form, or work.

World Resources

Application

Because of the instability and extreme toxicity of its oxide, osmium is not often used in its pure state, and is instead often alloyed with other metals. Those alloys are utilized in high-wear applications. Osmium alloys such as osmiridium are very hard and, along with other platinum group metals, are used in the tips of fountain pens, instrument pivots, and electrical contacts, as they can resist wear from frequent operation.