Djurleit
| Djurleit | |
|---|---|
 |
|
| General and classification | |
| chemical formula | Cu 31 S 16 |
|
Mineral class (and possibly department) |
Sulfides and sulfosalts |
|
System no. to Strunz and to Dana |
2.BA.05 ( 8th edition : II / B.01) 04/02/07/02 |
| Crystallographic Data | |
| Crystal system | monoclinic |
| Crystal class ; symbol | 2 / m |
| Space group | P 2 1 / n (No. 14, position 2) |
| Lattice parameters |
a = 26.897 Å ; b = 15.745 Å; c = 13.565 Å β = 90.13 ° |
| Formula units | Z = 8 |
| Twinning | often at [100] for rotations of 60 ° |
| Physical Properties | |
| Mohs hardness | 2.5 to 3 |
| Density (g / cm 3 ) | calculated: 5.749 |
| Cleavage | Please complete |
| colour | black |
| Line color | black-metallic |
| transparency | Opaque |
| shine | Metallic |
Djurleit is a moderately common mineral from the mineral class of sulfides and sulfosalts. It crystallizes in the monoclinic crystal system with the chemical composition Cu 31 S 16 or Cu 1.9375 S, i.e. a combination of the elements copper and sulfur . It forms compact, short, prismatic crystals up to 1.5 cm in size. With a Mohs hardness of 2.5 to 3, it is one of the soft materials that can be scratched with a copper coin.
Etymology and history
The mineral was discovered and described by Eugene S. Rooseboom in 1962. With the discovery he made explicit reference to a synthesis of Cu 31 S 16 , which S. Djurle had already succeeded in 1958. However, he wrote of Cu 1.96 S, a copper sulphide with a higher copper content. After Roosemboom had discovered the mineral in nature, he named the mineral after S. Djurle Djurleite (English spelling). Rooseboom stated that the main problem with the discovery of Djurleit was to distinguish it from chalcosine (chemically Cu 2 S). In 1967 the mineral was recognized by the International Mineralogical Association (IMA).
classification
Already in the now outdated, but still in use 8th edition of the mineral classification according to Strunz , the Djurleit belonged to the mineral class of "sulfides and sulfosalts" and there to the department of "sulfides with the molar ratio of metal: sulfur, selenium, tellurium> 1: 1", where together with Anilith , Chalkosin, Digenit , Geerit , Roxbyit , Spionkopit and Yarrowit the "copper sulfide group" with the system no. II / B.01 .
The 9th edition of Strunz's mineral systematics , which has been in effect since 2001 and is used by the IMA, also assigns the Djurleit to the class of "sulfides and sulfosalts" and there in the department of "metal sulfides, M: S> 1: 1 (mainly 2: 1) "a. This division is, however, further subdivided according to the predominant metals in the compound, so that the mineral is to be found according to its composition in the sub-division "with copper (Cu), silver (Ag), gold (Au)", where it is the only member forms the unnamed group 2.BA.05b .
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns the Djurleit to the class of "sulfides and sulfosalts" and there in the department of "sulfide minerals". Here it is together with Anilith, Chalkosin, Digenit, Geerit, Roxbyit and Spionkopit in the "Chalkosin group (formula: Cu 2-x S)" with the system no. 04/02/07 within the subsection " Sulphides - including selenides and tellurides - with the composition A m B n X p , with (m + n): p = 2: 1 ".
Crystal structure
Djurleit crystallizes monoclinically in the space group P 2 1 / n (space group number 14, position 2) with the lattice parameters a = 26.897 Å , b = 15.745 Å, c = 13.565 Å and β = 90.13 ° as well as eight formula units per unit cell .
It forms twins that are rotated 60 ° on the surface [100].
Education and Locations
Djurleit is classically associated with other copper, iron and copper iron sulphides ; Digenite (Cu 9 S 5 ), bornite (Cu 5 FeS 4 ), chalcocite (Cu 2 S), chalcopyrite (CuFeS 2 ), anilite (Cu 7 S ) have been observed 4 ) and pyrite (FeS 2 ).
Djurleit is found all over the world; 282 sites were reported (as of 2015). These are located in Argentina , in the Atlantic Ocean , Australia , Austria , Belgium , Brazil , Bulgaria , Canada , Chile , China , the Czech Republic , the Democratic Republic of the Congo , Finland , France , Germany , Greece , Greenland , Hungary , India , Indonesia , Ireland , Italy , Japan , Kazakhstan , Mexico , Namibia , Norway , Papua New Guinea , Peru , the Philippines , Poland , Portugal , Romania , Russia , Serbia , Slovakia , Spain , Sweden , Switzerland , Great Britain and the United States United States of America .
See also
literature
- HT Evans: The crystal structures of low chalcocite and djurleite In: Zeitschrift für Kristallographie , Vol. 150, 1979, pp. 299-320
- Mihály Pósfai, Peter R. Buseck: Djurleite, digenite, and chalcocite: Intergrowths and transformations In: American Mineralogist , Vol. 79, 1994, pp. 308–315 ( PDF )
Web links
- American-Mineralogist-Crystal-Structure-Database - Djurleite
- Database-of-Raman-spectroscopy - Djurleite
Individual evidence
- ↑ a b c d e f Djurleite , In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America , 2001 ( PDF )
- ^ Mineral Atlas: Djurleit
- ↑ a b Mindat: Djurleite
- ^ Eugene S. Rooseboom: Mineralogical Notes: Djurleite, Cu 1.96 S, a new mineral In: The American Mineralogist. Volume 47, September – October 1962 ( PDF )