Weishanite
Weishanite | |
---|---|
General and classification | |
other names |
IMA 1982-076 |
chemical formula | (Au, Ag) 3 Hg 2 |
Mineral class (and possibly department) |
Elements - metals and intermetallic alloys |
System no. to Strunz and to Dana |
1.AD.20 ( 8th edition : I / A.02) 01.01.08.06 |
Crystallographic Data | |
Crystal system | hexagonal |
Crystal class ; symbol | 6 / mmm |
Space group | P 6 3 / mmc |
Lattice parameters | a = 2.927 Å ; c = 4.818 Å Please complete the source as an individual reference |
Formula units | Z = 2 Please complete the source as an individual reference |
Physical Properties | |
Mohs hardness | 2.4 |
Density (g / cm 3 ) | 18.17 |
Cleavage | is missing |
colour | light yellow |
Line color | light yellow |
transparency | opaque |
shine | metallic |
Weishanite is a very rare mineral from the mineral class of elements, more precisely metals and intermetallic compounds . It crystallizes in the hexagonal crystal system with the chemical composition (Au, Ag) 3 Hg 2 and forms grains up to 30 μm in size, which assemble into irregularly shaped aggregates of 0.05 to 0.04 mm in size. The light yellow mineral is ductile and ductile.
Etymology and history
Weishanit was Li Yuheng, Ouyang Shan and Tian Peixue first time in 1984 in the type locality , the Poshan-silver mine in the county Tongbai the Chinese province of Henan found.
classification
In the Strunz system , weishanite is counted among the metals and intermetallic compounds, a subgroup of the elements. After the 8th edition , together with belendorffite , lead amalgam , eugenite , gold amalgam , kolymite , luanheit , moschellandsbergite , potarite , mercury , paraschachnerite and schachnerite form a group. In the 9th edition , it forms a subgroup of the mercury amalgam family with gold amalgam.
In the systematics according to Dana it forms with lead amalgam, gold amalgam, luanheit, moschellandsbergite, eugenite, schachnerite and paraschachnerite a subgroup (silver-amalgam alloys) of the metallic elements apart from the platinum metals .
Education and Locations
Weishanite forms in the silicified zone of silver-rich gold - silver deposits in biotite . It is associated with gold, silver, acanthite , pyrite , galena , sphalerite , pyrrhotite and scheelite .
In addition to the type locality, finds from Mariana in Brazil and Rožňava in Slovakia are known.
Crystal structure
Weishanite crystallizes in the hexagonal crystal system in the space group P6 3 / mmc with the lattice parameters a = 2.927 Å and c = 4.818 Å as well as two formula units per unit cell .
See also
Individual evidence
literature
- Weishanite. In: Anthony et al .: Handbook of Mineralogy , 1990, 1, 101 ( pdf ).
- Li Yuheng, Ouyang Shan, Tian Peixue: Weishanite - A new gold-bearing mineral. In: Acta Mineralogica Sinica , 1984, 4, 2, pp. 102-105 (Chinese). Abstract in: American Mineralogist , 1988, 73, p. 196 (English, pdf ).