Element Osmium, Os, Transition Metal

76
Os
190.2
Osmium

[Xe]
6s2
4f14
5d6

Osmium History

Transition metal Osmium was discovered in 1803 (and documented in 1804) by Tennant during his researches of platinum residue insoluble in aqua regia, which was identified later as two new elements, osmium and iridium. About the same time, Collet-Descotils suspected the existence of a new metal by the black powder formed by the dissolution of native platinum in aqua regia. Tennant separated osmium and iridium. The residue itself named osmiridium.

The name Osmium is after the Greek "scent, stench" because of the stark smell of chlorine or radish.

Osmium Occurrence

Osmium crustal abundance is 5x10-6 mass %. It is a rare traced element. The main minerals are some kinds of iridosmine such as nevyanskite and syssertskite. Beside osmium and iridium they contain also several other mineral forming elements and belong to the solid solutions class. Osmium occurs also as compounds with sulphur ans arsenic (erlichmanite, osmium-bearing laurite, osarsite). As an isomorphic impurity osmium is contained in chalcopyrite (copper pyrite), pyrrhotine, pentlandite, cubanite, also known as "chalmersite" and magnetite.

Osmium Neighbours


Complete Periodic Table