Renierite
| Renierite | |
|---|---|
 |
|
| General and classification | |
| other names |
formerly Reniérit |
| chemical formula | (Cu 1+ , Zn) 11 Fe 4 (Ge 4+ , As 5+ ) 2 S 16 |
|
Mineral class (and possibly department) |
Sulphides and sulphosalts - metal: sulfur (selenium, tellurium) = 1: 1 |
|
System no. to Strunz and to Dana |
2.CB.35 ( 8th edition : II / C.10) 02.09.04.01 |
| Similar minerals | Colusite, germanite, bornite |
| Crystallographic Data | |
| Crystal system | tetragonal, pseudocubic |
| Crystal class ; symbol | Scalenohedral 4 2 m |
| Space group | P 4 2 c (No. 112) |
| Lattice parameters | a = 10.6226 (5) Å ; c = 10.5506 (8) Å |
| Formula units | Z = 2 |
| Frequent crystal faces | {111} |
| Twinning | pronounced |
| Physical Properties | |
| Mohs hardness | 3.5 to 4.5 (VHN 25 = 340 to 363) |
| Density (g / cm 3 ) | measured: 4.38; calculated: 4.4 |
| Cleavage | no |
| Break ; Tenacity | uneven |
| colour | bronze brown, orange brown |
| Line color | dark gray |
| transparency | opaque |
| shine | Metallic luster |
| magnetism | moderate to clear, partly polar |
| Crystal optics | |
| Birefringence | δ = weak |
| Other properties | |
| Special features | polished surface often shows twins and anisotropy |
Renierite (formerly Reniérit ) is a rarely occurring mineral from the mineral class of " sulfides and sulfosalts ". It crystallizes in the tetragonal crystal system with the chemical composition (Cu 1+ , Zn) 11 Fe 4 (Ge 4+ , As 5+ ) 2 S 16 . The elements copper and zinc or germanium and arsenic indicated in the round brackets can represent each other in the formula ( substitution , diadochy), but are always in the same proportion to the other components of the mineral.
Renierite is mostly found in the form of granular to coarse mineral aggregates , but also develops small, irregular or cube-shaped crystals up to about three millimeters in size, with a bronze-brown to orange-brown color and a metallic sheen .
Etymology and history
The mineral was named after the Belgian geologist Armand Marie Vincent Joseph Renier (1876–1951).
The first find was described in 1928 as small, conspicuous grains in a sulfidic ore by G. Thorreau and misinterpreted. He compared the material to "orange bornite ". Later misinterpretations followed and the renierite was first correctly described in 1948 by Johannes Franciscus Vaes (1902–1978).
The spelling Reniérite , originally chosen by Vaes , has been discredited since 2008 because the namesake is written without an acute accent above the 'e' and is therefore an unnecessary diacritical mark .
The type locality is the Kipushi Mine ( coordinates ), formerly Prince Léopold Mine, Kipushi , Haut-Katanga Province , in the Democratic Republic of the Congo .
classification
In the meanwhile outdated, but still in use 8th edition of the mineral classification according to Strunz , the renierite belonged to the mineral class of "sulfides and sulfosalts" and there to the department of "sulfides with the molar ratio metal: sulfur, selenium, tellurium ≈ 1: 1", where he together with Colusit , Germanit , Germanocolusit , Maikainit , Morozeviczit , Nekrasovit , Ovamboit , Polkovicit , Stibiocolusit , Sulvanit and Vinciennit the "Colusitgruppe" with the system number. II / C.10 formed.
The 9th edition of Strunz's mineral systematics , which has been in effect since 2001 and is used by the International Mineralogical Association (IMA), assigns renierite to the class of “sulfides and sulfosalts” and there to the department of “metal sulfides, metal: sulfur = 1: 1 (and similar) ”. However, this section is further subdivided according to the predominant metals in the compound, so that the mineral can be found according to its composition in the sub-section "with zinc (Zn), iron (Fe), copper (Cu), silver (Ag)", where together with Catamarcait , Hemusit , Kiddcreekit , Morozeviczit, Polkovicit and Vinciennit the "Hemusitgruppe" with the system no. 2.CB.35.a forms.
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns renierite to the class of "sulphides and sulphosalts" and there to the category of "sulphide minerals". Here it is together with germanite , maikainite and ovamboite in the "germanite group" with the system no. 02.09.04 within the subsection " Sulphides - including selenides and tellurides - with the composition A m B n X p , with (m + n): p = 1: 1 ".
Crystal structure
Renierite crystallizes in the tetragonal crystal system in the space group P 4 2 c (space group no. 112) with the lattice parameters a = 10.62 Å and c = 10.55 Å as well as two formula units per unit cell . However, not all metal ion sites are fully occupied and copper can substitute for zinc. The structure can be written as a mixed crystal row between the end members Cu 10 ZnGe 2 Fe 4 S 16 and Cu 11 GeAsFe 4 S 16 . Zn (II) + Ge (IV) is replaced by Cu (I) + As (V).
properties
Renierite crystals simulate the higher symmetry of the cubic crystal system through polysynthetic twinning (repeated lamellar alignment). Such crystals are therefore called pseudocubic. The crystals, which are up to 3 mm in size, but usually grains in the sub mm range, appear as tetrahedra.
Education and Locations
Renierite is formed by hydrothermal processes in deposits containing germanium . Accompanying minerals include bornite , chalcopyrite , diginite , enargite , germanite, sphalerite and tennantite .
As a rare mineral formation, renierite could only be detected at a few sites, with around 30 sites being known to date (as of 2015). Its type locality Kipushi Mine is the only known site in the Democratic Republic of the Congo to date.
Other locations include Catamarca in Argentina ; Tasmania in Australia ; Dobrich (formerly Hajilogu Pasardschik ) in Bulgaria ; Provence-Alpes-Cote d'Azur in France ; in Sardinia in Italy ; on Honshū in Japan ; the Otjikotosee and the Otjozondjupa region in Namibia ; Salzburg and Styria in Austria ; in the northern Caucasus region in Russia ; in the Central Province of Zambia ; Asturias in Spain ; as well as Colorado in the USA .
use
Due to its germanium content of around 6%, renierite is important as a raw material for the extraction of this element.
See also
literature
- Renièrite. In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America. 2001 ( handbookofmineralogy.org PDF; 62 kB).
Web links
- Mineral Atlas: Renierite (Wiki)
- Database-of-Raman-spectroscopy - Renierite.
- American-Mineralogist-Crystal-Structure-Database - Renierite.
- Dissertation LR Bernstein: Aspects of Germanium Mineralogy and Geochemistry. Stanford University 1985.
Individual evidence
- ↑ a b IMA / CNMNC List of Mineral Names; May 2015 (PDF; 1.6 MB).
- ↑ a b Webmineral - Renierite. (English).
- ↑ a b c Lawrence R. Bernstein, Daniel G. Reichel, Stefano Merlino: Renierite crystal structure refined from Rietveld analysis of powder neutron-diffrection data. In: American Mineralogist. Volume 74, 1989, pp. 1177-1181 ( minsocam.org PDF; 599 kB).
- ↑ a b c Renièrite. In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America. 2001 ( handbookofmineralogy.org PDF; 62 kB).
- ↑ Stefan Weiß: The large Lapis mineral directory. All minerals from A - Z and their properties . 6th completely revised and supplemented edition. Weise, Munich 2014, ISBN 978-3-921656-80-8 .
- ↑ a b Joseph Murdoch: X-Ray Investigation of Colusite, Germanite and Renierite. In: American Mineralogist. Volume 24, 1953, pp. 794-801 ( minsocam.org PDF; 461 kB).
- ↑ L. Bernstein: Renierite, Cu 10 ZnGe 2 Fe 4 S 16 -Cu 11 GeAsFe 4 S 16 : a coupled solid solution series. In: American Mineralogist. Volume 71, 1986, pp. 210-221 ( minsocam.org PDF; 1.4 MB).
- ↑ G. Thorreau: Le Giement Prince Leopold, Kipushi, Katanga. In: Mem. De l'Inst. Geol. De l'Université de Louvain. Volume 4, Issue 3, p. 273.
- ↑ J. Murdoch, "Microscopical Determination of the Opaque Minerals, John Wiley & Sons, NY
- ↑ JF Vaes: La reniérite (anciennement applelee "Bornite orange") Un sulfure germanifère provenant de la Mine Prince Leopold, Kipushi (Congo Belge). In: Annales de la Société Géologique de Belgique. Volume 72, 1948, pp. 19-32.
- ^ Ernst AJ Burke: Tidying up Mineral Names: an IMA-CNMNC Scheme for Suffixes, Hyphens and Diacritical marks. In: Mineralogical Record. Volume 39, No. 2 (March – April 2008; pubsites.uws.edu.au PDF 2.7 MB).
- ↑ Mindat - Number of localities for Renierite.
- ↑ Find location list for renierite at the Mineralienatlas and at Mindat .
- ^ Friedrich Klockmann : Klockmanns textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke, Stuttgart 1978, ISBN 3-432-82986-8 , pp. 433 (first edition: 1891).