Cobalt (Co)
"The Blue Goblin, a hero who creates super-strong magnets and gives glass its beautiful deep blue color."
A memorable persona to anchor Co in your mind.
8.9
Grams per cm³
1495
Celsius (°C)
192
Radius (pm)
Daily Life Link
Cobalt is found in the deep blue color of a piece of glass art.
Discovery & History
Year Discovered
1735
Discovered By
Georg Brandt
Origin of Name
"The name is derived from the German word ''kobald'', meaning goblin."
Technical Properties
Atomic Mass
58.933 u
Standard State
solid
Boiling Point
2927°C
Electron Configuration
[Ar] 3d74s2
1st Ionization Energy
7.881 eV
Electron Affinity
N/A
Oxidation States
"Cobalt is a hard, brittle, silvery-blue magnetic metal."
Did You Know?
Its name comes from the German word 'kobold', which means 'goblin' or 'evil spirit', because miners in the Middle Ages found it would sicken them (due to arsenic in its ores) while yielding no valuable metal.
Cobalt is what gives the famous "cobalt blue" color to glass, ceramics, and pigments.
It is a critical component of Vitamin B12, the only vitamin known to contain a metal element.
Cobalt is used to create some of the strongest magnets in the world when alloyed with samarium or other rare earth elements.