Calamine (mineral)
- This article is about calamine in mineralogy. For calamine used in calamine lotion, see calamine, for other uses of the word, see calamine (disambiguation).
Calamine is a historic name for an ore of zinc. The name calamine was derived from the Belgian town of Kelmis, whose French name is "La Calamine", which is home to a zinc mine. In the 18th and 19th century large ore mines could be found near the German village of Breinigerberg.
During the late 18th century it was discovered that what had been thought to be one ore was actually two distinct minerals:
- Zinc carbonate ZnCO3 or smithsonite and
- Zinc silicate Zn4Si2O7(OH)2·H2O or hemimorphite.
The two minerals are usually very similar in appearance and can only be distinguished through chemical analysis. The first person to separate the minerals was the British chemist and mineralogist James Smithson in 1803. In the mining industry the term calamine is still used to refer to both minerals indiscriminately.
In mineralogy calamine is no longer considered a valid term. It has been replaced by smithsonite and hemimorphite in order to distinguish it from the pinkish mixture of zinc oxide (ZnO) and iron(III) oxide (Fe2O3) used in calamine lotion.
Until the 18th century, calamine was essential for the production of brass since metallic zinc does not exist in nature and no technique was known to produce it. Brass produced using calamine is called calamine brass.
See also
- Calamine, a mixture used in calamine lotion
- Smithsonite
- Hemimorphite