1) Iridosmine 2) Mineral 3) Superhard material 1) Iridosmine 
Osmiridium, also known as iridosmium or iridosmine, is a natural alloy of osmium and iridium, with traces of other platinum group metals. Osmiridium has been defined as containing a higher proportion of iridium, while iridosmine contains more osmium. However, as the content of the natural Os-Ir alloys varies considerably, the constituent percentag...
Osmiridium (iridosmine) is a naturally occurring alloy of osmium and iridium.
[n] - a hard and corrosion resistant mineral that is a natural alloy of osmium and iridium (usually containing small amounts of rhodium and platinum)
Osmiridium (iridosmine) is a naturally occurring alloy of osmium and iridium. Used to make long-wearing tips for gold fountain-pen nibs.
iridosmine noun a hard and corrosion resistant mineral that is a natural alloy of osmium and iridium (usually containing small amounts of rhodium and platinum); used in needles and pen nibs etc.
iridosmine.