76Os Osmium

Year Discovered


Discovered By

Smithson Tennant of England

Biological Rating

Not necessary for life.


Named from the Greek word meaning “smell,” osmium is a bluish-gray metal that is very stable, unaffected by air, water or acids. Powdered osmium gives off a distinctive, pungent smell, which is actually the compound osmium tetroxide. It is this smell that gives osmium its name. Osmium is densest of all elements; a brick-sized block would weigh about 56 pounds. Osmium is used to create extremely hard alloys. Ball-point pen tips, durable electrical contacts and high stress joints and pivots are usually made of an osmium alloy. Osmium tetroxide is used to detect fingerprints. A platinum-osmium alloy is used in pacemakers and heart replacement valves. Osmium also has use in microscopy and as a catalyst.

Biological Benefits

Osmium has no known biological use.

Role in Life Processes

No known benefits for life processes in plants and animals.


Osmium is found in its pure form, and natural alloy with iridium known as osmiridium and iridosmine. Osmium is concentrated in layered mafic igneous bodies with other platinum-group metals. It is recovered as a by-product of nickel processing, and is mined in South Africa, Russia, Canada, Australia and the USA.