Fletcherite is a rare thiospinel sulfide mineral

Sulfide mineral

The sulfide minerals are a class of minerals containing sulfide as the major anion. Some sulfide minerals are economically important as metal ores. The sulfide class also includes the selenides, the tellurides, the arsenides, the antimonides, the bismuthinides, the sulfarsenides and the sulfosalts...

 with formula Cu(Ni,Co)₂S₄. It is an opaque metallic steel gray mineral which crystallizes in the Cubic crystal system

Cubic crystal system

In crystallography, the cubic crystal system is a crystal system where the unit cell is in the shape of a cube. This is one of the most common and simplest shapes found in crystals and minerals....

. It is a member of the linnaeite

Linnaeite

Linnaeite is a cobalt sulfide mineral with the composition Co+2Co+32S4 . It was discovered in 1845 in Västmanland, Sweden, and was named to honor Carl Linnaeus ....

 group.

It was first described in 1977 for an occurrence in the Fletcher Mine, Viburnum Trend (New Lead Belt), near Centerville

Centerville, Missouri

Centerville is a city in Reynolds County, Missouri, along the West Fork of the Black River. The population was 171 at the 2000 census. It is the county seat of Reynolds County.-West Fork Lead Mine:...

, Reynolds County, Missouri

Reynolds County, Missouri

Reynolds County is a county located in the northwestern portion of the Ozark Foothills Region in Southeast Missouri in the United States. As of the 2000 U.S. Census, the county's population was 6,689. A 2008 estimate, however, showed the population to be 6,388. Its county seat is Centerville...

.

It occurs as a dissemination within copper sulfide minerals in mineralization replacing dolostone

Dolostone

Dolostone or dolomite rock is a sedimentary carbonate rock that contains a high percentage of the mineral dolomite. In old U.S.G.S. publications it was referred to as magnesian limestone. Most dolostone formed as a magnesium replacement of limestone or lime mud prior to lithification. It is...

 at the type locality

Type locality (geology)

Type locality , also called type area or type locale, is the where a particular rock type, stratigraphic unit, fossil or mineral species is first identified....

 in the Fletcher
mine where it is associated with vaesite

Vaesite

Vaesite is a mineral found together with cattierite in the Democratic Republic of Congo. It is named after Johannes F. Vaes, a Belgian mineralologist.-References:**...

, pyrite

Pyrite

The mineral pyrite, or iron pyrite, is an iron sulfide with the formula FeS2. This mineral's metallic luster and pale-to-normal, brass-yellow hue have earned it the nickname fool's gold because of its resemblance to gold...

, covellite

Covellite

Covellite is a rare copper sulfide mineral with the formula CuS. This indigo blue mineral is ubiquitous in copper ores, it is found in limited abundance and is not an important ore of copper itself, although it is well known to mineral collectors.The mineral is associated with chalcocite in zones...

, chalcopyrite

Chalcopyrite

Chalcopyrite is a copper iron sulfide mineral that crystallizes in the tetragonal system. It has the chemical composition CuFeS2. It has a brassy to golden yellow color and a hardness of 3.5 to 4 on the Mohs scale. Its streak is diagnostic as green tinged black.On exposure to air, chalcopyrite...

, bornite

Bornite

Bornite is a sulfide mineral with chemical composition Cu5FeS4 that crystallizes in the orthorhombic system .-Appearance:Bornite has a brown to copper-red color on fresh surfaces that tarnishes to various iridescent shades of blue to purple in places...

 and digenite

Digenite

Digenite is a copper sulfide mineral with formula: Cu9S5. Digenite is a black to dark blue opaque mineral that crystallizes with a trigonal - hexagonal scalenohedral structure. In habit it is usually massive, but does often show pseudo-cubic forms. It has poor to indistinct cleavage and a brittle...

. In an occurrence in Kalgoorlie, Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 it is found in black slate

Slate

Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism. The result is a foliated rock in which the foliation may not correspond to the original sedimentary layering...

 associated with pyrrhotite

Pyrrhotite

Pyrrhotite is an unusual iron sulfide mineral with a variable iron content: FeS . The FeS endmember is known as troilite. Pyrrhotite is also called magnetic pyrite because the color is similar to pyrite and it is weakly magnetic...

.