The etymology of covellite is interesting. The name comes from the Italian chemist and mineralogist Giuseppe Covelli (1809-1879), who first described the mineral in 1845. He found it in the "Codalunga" mine in Tuscany, Italy.
He described the mineral with the name "covellina" (in Italian) due to its dark blue-gray color similar to that of azurite (known in Italian as "covellino"), and he is the discoverer of the mineral .
The denomination "Covellite" was first used in 1845 by James Dwight Dana and Johannes Müller in Germany in their work "System of Mineralogy" and has become the standard denomination for the mineral in question.
This is how covellite, a rare mineral, finds itself with a name that pays homage to its discoverer, an Italian chemist and mineralogist
Covellite is a copper sulfide mineral species:
Covellite is a copper sulfide (CuS) that occurs as hexagonal or octahedral crystals.
It has a dark blue-gray to black color and is often opaque.
Covellite is a rather rare mineral and usually forms in sulphide deposits associated with other minerals such as chalcopyrite and bornite.
It is often found in hydrothermal deposits and may be associated with copper deposits.
Covellite has been used for copper production in the past, but today it is used primarily as a collectible mineral.
Covellite is found in several places around the world, including Montana in the United States. There are numerous covellite deposits in the state, including Silver Bow, Meagher, and Jefferson counties. Some of the best known sites include Boulder Mine, Cuprite Mine and Williams Mine.
The Boulder Mine, located near Butte, was once one of the nation's largest copper producers and produced large quantities of covellite throughout its history. The Cuprite mine, located in the Little Belt Mountains, also produced covellite as well as other copper minerals such as chalcopyrite and bornite. The Williams Mine, located in the Rocky Mountains, was mined for its covellite and other copper minerals.
It is important to note that the mines mentioned are now all closed and visits are prohibited, they are no longer in operation and it is important to respect private property and safety rules.
Covellite is a mineral hard enough for cabochon cutting, degree of hardness 3.5 to 4 on the Mohs scale. This means that it is strong enough to resist scratches and wear, but it can be a little tricky for a lapidary to carve due to its fragility. Covellite crystals tend to be quite brittle and can break easily when cut or polished.
It is important to take care when cutting and polishing covellite, using proper tools and techniques to avoid breaking the crystals. It is also advisable to use tools and techniques that reduce friction and heat to avoid causing internal cracks or inclusions.
Experienced lapidaries can effectively cut and polish covellite specimens, creating unique and aesthetically pleasing pieces that showcase the colors and shapes of the mineral.
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