Wikijunior:The Elements/Cobalt

Shows the position of Cobalt on the periodic chart.

Cobalt's symbol on the Periodic Table

What does it look, feel, taste, or smell like?

Pure (99.9 %) cobalt chips, electrolytically refined, and a high purity (99.8 % ) 1 cm3 cobalt cube for comparison.

Cobalt in its pure form is a hard, shiny silvery gray metal.

How was it discovered?

Cobalt has been known since ancient times.

Where did its name come from?

Did You Know?

• Cobalt has been used to color glass since the Bronze Age.
• Cobalt is a ferromagnetic metal.

The name Cobalt is from the German kobalt, corresponding to our word kobold, referring to a sort of goblin that lives in underground mines.

Where is it found?

The biggest source of cobalt ores is Katanga Province in the Democratic Republic of the Congo, in Africa, in the Tenke Fungurume mine. It can also be found when atoms go into nuclear fission (break apart).

What are its uses?

From ancient times, cobalt was mainly used as a blue pigment in glass, ceramics, and glazes. Today it is mainly used in making very strong alloys.

Is it dangerous?

Yes. Ingesting even rather small amounts of cobalt can cause serious health problems. Back in the 1960s, some people in Canada had heart problems — and several died — apparently caused by a cobalt compound used to stabilize beer foam. Very tiny amounts of cobalt are actually needed for life; there's a little cobalt in Vitamin B₁₂; but it's very rare for someone to have too little cobalt in their body.

Some people have an allergic skin reaction to contact with cobalt.