|
What the name
means: Chromium comes from the Greek
word khroma (or chroma)
meaning colour.
Who identified
chromium? In 1761 a German geologist
called Johann Gottlob Lehmann, while
working in gold mines in the Ural Mountains
of Siberia, made observations on a mineral
that he believed was a form of red lead.
The mineral became known as Siberian red
lead. Lehmann’s work was short lived (he
died in a chemical explosion in 1767) but
before the accident he did communicate his
observations to Georges-Louis Leclerc,
Comte de Buffon, which is why we know about
Lehmann’s part in the story.
The mineral that Lehmann
studied was not, in fact, red lead,
Siberian or otherwise, but an ore called
crocoite, that contains a compound made
from lead, chromium and oxygen. In 1770 a
German biologist, Peter Simon Pallas, while
on an expedition to the Ural Mountains,
discovered the value of crocoite ore in
providing pigments for paints. The bright
yellow colour it gave to paint became
extremely fashionable.
In 1797, Nicolas-Louis
Vauquelin, while working for the Comte de
Fourcroy, was successful in isolating the
new element from crocoite. At the
suggestion of the Comte de Fourcroy and the
mineralologist René Just Haüy, he called
the new element chromium on account of the
many different colours it produced when it
reacted with various chemicals.
About chromium:
Chromium is a hard, silvery looking
metal. It is mostly mined as chromite, a
compound of chromium and oxygen with iron
and magnesium. Free chromium is rare in
nature but it can be found in certain mines
in Russia, particularly where there are
diamonds.
Chromium metal is mostly
used mixed with other metals to form
alloys. Since it is a hard metal it can
help strengthen other metals. It is also
necessary in trace amounts in the human
body where, as the Cr3+ ion, it
is essential for insulin to function
correctly in regulating the body’s sugar
levels. |
The Open Door Web Site 
