Krut'aite or krutaite is a rare

mineral In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. ( ...

with the formula Cu Se₂. It crystallises in the

cubic crystal system In crystallography, the cubic (or isometric) crystal system is a crystal system where the Crystal_structure#Unit_cell, unit cell is in the shape of a cube. This is one of the most common and simplest shapes found in crystals and minerals. There ...

. It 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, being composed of Cu²⁺ ions and Se₂²⁻ ions. The mineral is most often found as a dark grey aggregate consisting of tiny crystals no more than a millimeter in size. The crystals are opaque in any size. It has no industrial use, but it is a prized collector's item.

Etymology and history

Krut'aite was first discovered in Petrovice in Okres Žďár nad Sázavou,

Czech Republic The Czech Republic, or simply Czechia, is a landlocked country in Central Europe. Historically known as Bohemia, it is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the southeast. The ...

and described in 1972 by Zdenek Johan, Paul Picot, Roland Pierrot and Milan Kvaček. It was named after the Czech mineralogist and director of the mineralogical laboratory of the

Moravian museum Moravian is the adjective form of the Czech Republic region of Moravia, and refers to people of ancestry from Moravia. Moravian may also refer to: * a member or adherent of the Moravian Church, one of the oldest Protestant denominations * Moravia ...

, Tomáš Krut'a (1906–1998). Since Krut'a is officially spelled with a Ť, the mineral is written correctly as Krut'aite, according to the rules established by the IMA. In older publications, the apostrophe is omitted entirely.

Occurrence

Krut'aite forms through hydrothermal processes and is often associated 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 ...

eskebornite Eskebornite is a selenide mineral with the formula Cu Fe Se2. It crystallizes in the tetragonal system and it has a brassy colour. Eskebornite is sometimes found as thick tabular crystals, but is more often found intergrown with other selenides ...

berzelianite Berzelianite is a rare copper selenide mineral with the formula Cu2 Se. It occurs as thin dendritic crusts or as fine-grained inclusions. It crystallizes in the isometric system, unlike its dimorph, bellidoite, which crystallizes in the tetrag ...

uraninite Uraninite, formerly pitchblende, is a radioactive, uranium-rich mineral and ore with a chemical composition that is largely UO2 but because of oxidation typically contains variable proportions of U3O8. Radioactive decay of the uranium causes t ...

hematite Hematite (), also spelled as haematite, is a common iron oxide compound with the formula, Fe2O3 and is widely found in rocks and soils. Hematite crystals belong to the rhombohedral lattice system which is designated the alpha polymorph of . ...

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 ...

bukovite Bukovite is a rare selenide mineral with formula Tl2Cu3FeSe4. It is a brown to black metallic mineral which crystallizes in the tetragonal system. It was first described in 1971 for an occurrence in the Bukov uranium mine, Rožná deposit, Vyso� ...

umangite Umangite is a copper selenide mineral, Cu3 Se2, discovered in 1891. It occurs only in small grains or fine granular aggregates with other copper minerals of the sulfide group. It has a hardness of 3. It is blue-black to red-violet in color with a ...

chalcopyrite Chalcopyrite ( ) is a copper iron sulfide mineral and the most abundant copper ore mineral. It has the chemical formula CuFeS2 and crystallizes in the tetragonal system. It has a brassy to golden yellow color and a hardness of 3.5 to 4 on the Mo ...

and

goethite Goethite (, ) is a mineral of the diaspore group, consisting of iron(III) oxide-hydroxide, specifically the "α" polymorph. It is found in soil and other low-temperature environments such as sediment. Goethite has been well known since ancient t ...

. It forms a

solid solution A solid solution, a term popularly used for metals, is a homogenous mixture of two different kinds of atoms in solid state and have a single crystal structure. Many examples can be found in metallurgy, geology, and solid-state chemistry. The word ...

series with

trogtalite Trogtalite is a rare selenide mineral with the formula Co Se2. It crystallizes in the cubic system and is part of the pyrite group, consisting of Co2+ and Se22− ions. It has a rose-violet colour and its crystals are opaque. It often occurs as ...

. It was first identified in Petrovice, Okres Žďár nad Sázavou,

, which is the only known locality in the Czech republic for the mineral, but it has since been identified in other places in the world. Notable is the El Dragón Mine,

Antonio Quijarro Province Antonio Quijarro is a province in the central parts of the Bolivian Potosí Department situated at the Salar de Uyuni. Its seat is Uyuni. Location Antonio Quijarro province is one of sixteen provinces in the Potosí Department. It is located be ...

Bolivia , image_flag = Bandera de Bolivia (Estado).svg , flag_alt = Horizontal tricolor (red, yellow, and green from top to bottom) with the coat of arms of Bolivia in the center , flag_alt2 = 7 × 7 square p ...

, where crystals up to a millimeter in size have been found. Other localities include: Weintraube Mine, Lerbach, Rosenhof veins,

Clausthal-Zellerfeld Clausthal-Zellerfeld is a town in Lower Saxony, Germany. It is located in the southwestern part of the Harz mountains. Its population is approximately 15,000. The City is the location of the Clausthal University of Technology. The health resort ...

Harz 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 ...

Lower Saxony Lower Saxony (german: Niedersachsen ; nds, Neddersassen; stq, Läichsaksen) is a German state (') in northwestern Germany. It is the second-largest state by land area, with , and fourth-largest in population (8 million in 2021) among the 16 ...

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

. Tumiñico Mine, Sierra de Cacho,

Villa Castelli Villa Castelli is a ''comune'' in the province of Brindisi in Apulia, on the south-east Italy coast. It is a comune in Salento, the borderline with Itria Valley. Its main economic activities are tourism and the growing of olives and grapes. Main ...

, General La Madrid department,

La Rioja La Rioja () is an autonomous community and province in Spain, in the north of the Iberian Peninsula. Its capital is Logroño. Other cities and towns in the province include Calahorra, Arnedo, Alfaro, Haro, Santo Domingo de la Calzada, and N� ...

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

. Yutangba Selenium deposit, Enshi Co.,

Enshi Tujia and Miao Autonomous Prefecture Enshi Tujia and Miao Autonomous Prefecture () is located in the mountainous southwestern corner of Hubei province, People's Republic of China. It forms Hubei's southwestern "panhandle", bordering on Hunan in the south and Chongqing Municipality i ...

(E'xi Autonomous Prefecture),

Hubei Province Hubei (; ; alternately Hupeh) is a landlocked province of the People's Republic of China, and is part of the Central China region. The name of the province means "north of the lake", referring to its position north of Dongting Lake. The prov ...

China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...

References

{{Reflist Selenide minerals Copper(II) minerals

Etymology and history

Occurrence

See also

References