Tiemannite

Tiemannit ( selenium mercury ) is a relatively rare occurring mineral from the mineral class of " sulfides and sulfosalts ." It crystallizes in the cubic crystal system with the chemical composition HgSe and developed predominantly granular to massive aggregates, but also well-educated, ideomorphe crystals of lead- gray to steel-gray or brownish in color.

Etymology and history

Was first found and described Tiemannit of Ferdinand Tiemann (1848-1899), a Berlin chemist, after which it is named.

Classification

In the now outdated but still in use 8th edition of the mineral classification by Strunz the Tiemannit belonged to the mineral class of " sulfides and sulfosalts " and then to the Department of " sulfides with the molar ratio of metal: sulfur, selenium, tellurium = 1:1", where he alone " Sphaleritgruppe " formed together with Coloradoite, Hawleyit, Rudashevskyit, Metacinnabarit, Polhemusit, sphalerite and Stilleit.

The 9th edition used since 2001 and valid by the International Mineralogical Association (IMA ) of the Strunz'schen Mineral classification assigns the Tiemannit also in the class of " sulfides and sulfosalts " and there in the department of "Metal Sulfides, M: S = 1: 1 ( and similar ) " a. This division, however, is further subdivided according to the dominant in the metal compound, so that the mineral according to its composition in the subsection " with zinc (Zn ), iron ( Fe), copper (Cu), silver (Ag ), etc., " Finding is where it is. together with Coloradoite, Hawleyit, Metacinnabarit, Polhemusit, Rudashevskyit, Sakuraiit, sphalerite and Stilleit the still existing " Sphaleritgruppe " with the system no 2.CB.05 forms.

The mainly common in English-speaking classification of minerals according to Dana assigns the Tiemannit into the class of " sulfides and sulfosalts " and there in the department of " sulfide minerals ." Here he is with Coloradoite, Hawleyit, Metacinnabarit, Rudashevskyit, sphalerite and Stilleit in the " Sphaleritgruppe ( Isometric: ) " with the system no. 02:08:02 within the subdivision " sulfides - tellurides and selenides, including - with the composition AmBnXp, with (m n): p = 1:1" to find.

Modifications and varieties

The variety Lerbachit (Hg, Pb ) Se, named after the mountain resort type locally Lehrbach, which consists of a mixture of Clausthalite and Tiemannit

Education and Locations

Tiemannit forms in hydrothermal veins. Accompanying minerals are other selenides as Clausthalite, Eukairit, Naumannite, Klockmannit and Umangit, other sulfides such as Metacinnabarit, galena and sphalerite, and barite and calcite.

Locations include La Rioja in Argentina; Western Australia in Australia; Luxembourg province of Belgium; Potosí Department in Bolivia; Gansu, Guizhou, Hunan and Sichuan in the People's Republic of China; Bavaria, Lower Saxony, Rhineland -Palatinate, Saxony and Stangerode / Saxony- Anhalt in Germany; Devon in England; Saskatchewan in Canada; Queretaro and Sonora in Mexico; Silesia in Poland; in the eastern regions of Siberia in Russia; Bohemia and Moravia in the Czech Republic; as well as California, Nevada and Utah in the United States.

Crystal structure

Tiemannit crystallizes in the cubic crystal system in the space group with the lattice parameters a = 6.085 Å and four formula units per unit cell.

Use

Tiemannit is true for about 72 % of mercury and about 28 % of selenium, however, is technically insignificant due to its rarity as a raw material for these elements.