Covellite is a Copper Sulfide that is a rare and uncommon mineral. It is probably the deepest Indigo-Blue metallic color you will ever find. Covellite is not a well known mineral and it is difficult and expensive to obtain specimens. It is said that “Covellite’s iridescent allure can capture the hearts of anyone that looks into the deep indigo blue colors”. It is normally a deep metallic indigo blue that when tarnished turns a purple or black with iridescent yellow and red flashes. Covellite normally will have spotting or veining of Pyrite throughout and may include the host matrix or quartz. Covellite cuts fairly easy and is stable after cutting. The Leonard Mine in Butte, Montana was the world’s leading producer of Covellite until its closure in the 1930's. Butte is located close to the Continental Divide at an elevation of 5549 feet in the Rocky Mountains. The Leonard Mine was a major producer of chalcocite-enargite ores from the central ore zone and is a well known mineral specimen producer.
Covellite was mined at a depth of up to 3,300 feet and was reported at one location to be in a vein 3 feet wide. This material is super rare and hard to find and is highly valued and prized by collectors and cutters around the world. Mineral specimens of Covellite from Butte can only be matched in quality by specimens from Summitville, Colorado. Butte has notably provided more Covellite mineral specimens than any locality in the world.
Covellite was the first known natural superconductor, and its properties have many industrial applications. Attempts to synthesize Covellite have not been successful due to the numerous and complex processes that must take place for the formation of Covellite. The scarcity of Covellite and the closure of the mine since the 1930's have resulted in a current pricing of specimens starting at around $250.00 per pound ($15.63/oz) or $0.55 per gram, which is equivalent to the pricing on many meteorites.
Covellite is also known as Blue Copper, Covellonite, Covelline, Covellinite, Blue Indigo, Indigo Copper and Breithauptite (of Chapman).
Indigo Blue Covellite from the Leonard Mine
Large Leonard Mine Covellite display specimen.
This specimen is from our personal collection and is a beautiful example of old stock covellite as seen in the tarnish colorings seen in the sunlight. When this specimen is indoors, it is seen as a deeper indigo with less irridescence. The amount of irridescence seen depends upon the amount of light shining on the display specimen. This is a very solid piece with about 15% quartz matrix by volume, but is over 95% covellite by weight. In addition to the indigo blue iridescent sheen, it has flashes of the classic deep red and purple. This piece has veins and spots of pyrite and will be an excellent addition to any collection.
This specimen weighs 1.61 lbs (25.9 oz) 732g and measures 3.7 x 3.3 x 2.1 inches (9.5 x 8.4 x 5.4cm)