Hunchunit
| Hunchunit | |
|---|---|
| General and classification | |
| other names |
IMA 1991-033 |
| chemical formula | Au 2 Pb |
|
Mineral class (and possibly department) |
Elements - metals and intermetallic alloys |
|
System no. to Strunz and to Dana |
1.AA.25 ( 8th edition : I / A.01) 01.01.04.02 |
| Crystallographic Data | |
| Crystal system | cubic |
| Crystal class ; symbol | cubic hexakisoctahedral; 4 / m 3 2 / m |
| Space group | Fd 3 m (No. 227) |
| Lattice parameters | a = 7.93 Å |
| Formula units | Z = 8 |
| Physical Properties | |
| Mohs hardness | 3.5 |
| Density (g / cm 3 ) | calculated: 15.99 |
| Cleavage | Please complete |
| colour | silver gray to lead gray |
| Line color | Please complete |
| transparency | opaque |
| shine | Metallic luster |
Hunchunit is a very rarely occurring mineral from the mineral class of elements, more precisely metals and intermetallic compounds . It crystallizes in a cubic crystal system with the chemical composition Au 2 Pb, i.e. it consists of gold and lead in a molar ratio of 2: 1.
Hunchunit forms granular aggregates that are fused with solid gold and lead as well as anyuiite .
Etymology and history
Hunchunit was first found in 1992 by Wu Shangquan, Yang Yi and Song Qun in the type locality , the Sandaogou gold field near Hunchun in Jilin Province in the People's Republic of China . It is named after the Hunchun River on which the type locality is located.
classification
In the outdated, but partly still in use, 8th edition of the mineral classification according to Strunz , the Hunchunit belonged to the department of "Metals and intermetallic alloys (without semimetals)", where together with Anyuiit , Auricuprid , Bogdanovit , gold, copper , Novodneprit , silver , Tetra-Auricuprid , Yuanjiangit the "copper series" with the system no. I / A.01 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), also classifies the Hunchunit in the “Metals and Intermetallic Compounds” department. However, this is further subdivided according to the metals predominating in the compound, which have been divided into metal families according to their related properties. According to its composition, Hunchunit can be found in the subdivision "Copper Cupalite Family", where it is the only member of the unnamed group 1.AA.25 .
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns the Hunchunit to the class and department of the same name of "elements". Here he is together with Anyuiit and Novodneprit in the group " Anyuiit and related alloys " with the system no. 01.01.04 within the sub-section "Elements: Metallic elements other than the platinum group".
Crystal structure
Hunchunit crystallizes in the cubic crystal system in the space group Fd 3 m (space group no. 227) with the lattice parameter a = 7.933 Å , and eight formula units per unit cell .
Education and Locations
Hunchunit is found in gold deposits. It is associated with gold, lead, anyuiite, pyrite , pyrrhotite , magnetite and ilmenite . Finds are so far only known from the type locality.
See also
literature
- Hunchunite . 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; 60 kB ; accessed on September 7, 2017]).
- Shangquan Wu, Yi Yang, Qun Song: A new gold mineral-hunchunite (Au 3 Pb) . In: Acta Mineralogica Sinica . tape 12 , no. 4 , 1992, pp. 319-322 (Chinese).
- John Leslie Jambor , Edward S. Grew, Andrew C. Roberts: New Mineral Names. Hunchunite . In: American Mineralogist . tape 79 , 1994, pp. 1210 ( minsocam.org [PDF; 581 kB ; accessed on September 7, 2017]).
Web links
Individual evidence
- ^ A b Hugo Strunz , Ernest H. Nickel : Strunz Mineralogical Tables. Chemical-structural Mineral Classification System . 9th edition. E. Schweizerbart'sche Verlagbuchhandlung (Nägele and Obermiller), Stuttgart 2001, ISBN 3-510-65188-X , p. 36 .
- ↑ Hunchunite . 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; 60 kB ; accessed on September 7, 2017]).