Osmium

Real Metals · Very Rare · Modern

The densest element in the periodic table, osmium is so rare that the entire world's annual production would fit in a coffee cup. Its extreme density makes a block of osmium feel almost unreal, far heavier than the eye expects.

Identity

Symbol
Os
Atomic number
76
Source
Natural element
Aliases
Os

Physical Properties

Appearance
Blue-grey, hard, brittle; the densest naturally occurring element known
Luster
Metallic
Density
22.59 g/cm³
Melting point
3033 °C
Boiling point
5012 °C
Lighter
Iridium
Magnetism
Non-magnetic
Electrical conductivity
Medium

Mechanical Properties

Mohs hardness
7
Tensile strength
500 MPa
Softer
Vanadium
Harder
Tungsten
Workability
Difficult
Brittleness
Brittle
Malleability
Very Low
Ductility
Very Low

Chemical Properties

Corrosion resistance
very high
Reactivity
low

Lore & Narrative

Its name comes from the Greek osme, 'smell', because osmium tetroxide, produced when osmium oxidizes, has a distinctive acrid odor. This compound is also severely toxic, making osmium uniquely dangerous in powdered or oxidizing forms.

Notable uses
Pen tips, compass needles, electrical contacts, scientific instruments
Forge uses
precision instruments, electrical contacts
Worldbuilding traits
densest, rare, toxic-oxide, extreme

Browse the Metal Encyclopedia — MGS Toolbox