Trogtalite is a rare

selenide mineral Selenide minerals are those minerals that have the selenide anion as a main component. Selenides are similar to sulfides and often grouped with them. Examples include: * achavalite * athabascaite * clausthalite * ferroselite * penroseite ...

with the formula Co Se_2. It crystallizes in the cubic system and is part of the

pyrite The mineral pyrite (), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Iron, FeSulfur, S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral. Pyrite's metallic Luster (mineralogy), lust ...

group, consisting of Co²⁺ and Se₂²⁻ ions. It has a rose-violet colour and its crystals are opaque. It often occurs as grains. It was thought to be dimorphous with hastite, but this was discredited in 2009. Hastite turned out to be the iron selenide mineral

ferroselite Orthorhombic ferroselite and its isometric polymorph dzharkenite are iron selenides of general formula FeSe2 precipitated under reducing conditions in anoxic environments. They are a source of selenium in the Rocky Mountains where selenium occ ...

. It forms a solid solution series with

krut'aite Krut'aite or krutaite is a rare mineral with the formula Cu Se2. It crystallises in the cubic crystal system. It is part of the pyrite group, being composed of Cu2+ ions and Se22− ions. The mineral is most often found as a dark grey aggregate c ...

Occurrence

Trogtalite was first found in 1955 in Trogtal quarry,

Lautenthal The formerly free mining town ('' Bergstadt'') of Lautenthal in Germany is a state-recognised, climatic spa with around 1,570 inhabitants and has been part of the borough of Langelsheim since 1972. Geography Lautenthal lies in the Innerst ...

Harz Mountains The Harz () is a highland area in northern Germany. It has the highest elevations for that region, and its rugged terrain extends across parts of Lower Saxony, Saxony-Anhalt, and Thuringia. The name ''Harz'' derives from the Middle High German ...

, Germany, after which it was also named. It often occurs intergrown with

clausthalite Clausthalite is a lead selenide mineral, PbSe. It forms a solid solution series with galena PbS. Occurrence It occurs in low-sulfur hydrothermal deposits with other selenides and in mercury deposits. It is associated with tiemannite, klockmann ...

grains at this locality. It has also been found in the Musonoi Cu–Co mine,

Kolwezi Kolwezi or Kolwesi is the capital city of Lualaba Province in the south of the Democratic Republic of the Congo, west of Likasi. It is home to an airport and a railway to Lubumbashi. Just outside of Kolwezi there is the static inverter plant of ...

Katanga Province Katanga was one of the four large provinces created in the Belgian Congo in 1914. It was one of the eleven provinces of the Democratic Republic of the Congo between 1966 and 2015, when it was split into the Tanganyika Province, Tanganyika, Hau ...

, Congo and in Argentina, in Tuminico, Sierra de Cacho, and in Los Llantenes, La Rioja Province. It is often found together with clausthalite,

, bornhardtite, native selenium,

gold Gold is a chemical element with the symbol Au (from la, aurum) and atomic number 79. This makes it one of the higher atomic number elements that occur naturally. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile met ...

, and

oosterboschite Oosterboschite is a rare selenide mineral with the formula . It crystallises in the orthorhombic crystal system. It has a creamy yellow colour and a Moh's hardness of 5. It is often found as grains with no clear shape. The crystals are opaque and ...

References

{{reflist Selenide minerals Cobalt minerals Cubic minerals Minerals in space group 205

Occurrence

See also

References