Stromeyerite
- Cypargyrit
- Copper Silver Gloss
- Silver chalcocite
Stromeyerite ( Cypargyrit, copper silver luster ) is a rarely occurring mineral from the mineral class of sulfides and sulfosalts. It crystallizes in the orthorhombic crystal system with the chemical formula AgCuS and usually forms massive, disseminated, massive aggregates of steel-gray color, which turn blue. Rarely does one find even prismatic crystals up to 5 mm in size. In addition to copper and silver may also contain traces of iron.
Etymology and history
The mineral was first discovered in 1832 by François Sulpice Beudant in the type locality Vrančice in Příbram (Czech Republic). The first chemical investigation was carried out by the Göttingen professor of chemistry Friedrich Stromeyer, after the mineral is named.
Classification
In the classification by Strunz Stromeyerite is classified in the sulfides and sulfosalts. It is added to the metal sulfides with a ratio of metal to sulfur of> 1: 1 are counted. In the 8th edition he made with Brodtkorbit, Eukairit, Henryit, Imiterit, Jalpaite, Selenojalpait and Mckinstryit a group. In the 9th edition of the sulfides are further subdivided according to cations, there is Stromeyerite together with Mckinstryit in a group of sulfides with copper ( Cu), silver (Ag ) or gold ( Au) to find.
In the scheme of minerals by Dana Stromeyerite forms with Eukairit a subset of the sulfides - tellurides and selenides, including - with the composition AmBn Xp, with (m n): p = 2:1.
Education and Locations
Stromeyerite usually forms as a secondary mineral under hydrothermal conditions. Also a formation as a primary mineral is possible. The mineral is associated with Freibergite, bornite, chalcopyrite, galena and other sulfide minerals.
Worldwide Stromeyerite could be proven so far to about 300 localities (as of 2010). Apart from its type locality Vrančice, more precisely in the local pit " Alexander", the mineral became apparent in the Czech Republic still in Radětice in Příbram, Jáchymov and in the uranium deposit of Reichenberg ( Liberec Region ) region. The largest deposits are, however, in the United States, particularly in Arizona, Colorado and Montana.
Known localities in Germany are far Hausach - Hechtsberg and the Clara mine in Baden- Württemberg, Waidhaus Hagen village in Bavaria, the pit Victoria in the winning country (NRW), the Mansfeld Basin, Saxony -Anhalt and Berggießhübel and Freiberg in Saxony's Erzgebirge.
In Switzerland Stromeyerite in a study conducted by the NAGRA bore near Kaisten in the canton of Aargau, on the Mürtschenalp in the canton of Glarus, in the Grisons Val Curnera as well as in the pit " Les Moulins " at Saint- Luc was found in the canton of Valais.
The only known locality in Austria is the Erasmus studs at Schwarzleo ( Leogang ) in the province of Salzburg.
Other localities lie among others in Argentina, Australia, Bolivia, Chile, China, France, Canada, Kazakhstan, Mexico, Norway, Poland and Russia.
Crystal structure
Stromeyerite crystallizes in the orthorhombic space group Cmc21 ( Raumgruppen-Nr. 36) with the lattice parameters a = 4.06 Å, b = 6.62 Å and c = 7.97 Å and four formula units per unit cell.
Use
Stromeyerite is a raw material for the recovery of elemental copper and silver.