Paraschachnerite
| Paraschachnerite | |
|---|---|
| General and classification | |
| chemical formula | Ag 3 Hg 2 |
|
Mineral class (and possibly department) |
Elements - metals and intermetallic alloys |
|
System no. to Strunz and to Dana |
1.AD.15 ( 8th edition : I / A.02) 1.1.8.3 |
| Crystallographic Data | |
| Crystal system | orthorhombic |
| Crystal class ; symbol | mmm or mm 2 |
| Space group | Cmcm or Cm 2 |
| Lattice parameters | a = 2.916 Å ; b = 5.13 Å; c = 4.83 Å Please complete the source as an individual reference |
| Formula units | Z = 2 Please complete the source as an individual reference |
| Twinning | always, along {110} |
| Physical Properties | |
| Mohs hardness | 4th |
| Density (g / cm 3 ) | 12.98 |
| Cleavage | Please complete |
| colour | tin-white metallic |
| Line color | silver-white metallic |
| transparency | opaque |
| shine | metallic |
Paraschachnerite is a very rare mineral from the mineral class of the elements, more precisely the metals and intermetallic compounds . It crystallizes in the orthorhombic crystal system with the chemical composition Ag 3 Hg 2 and forms crystals up to 1 cm in size. These are always complex twinned with the twin level {110}, triplets are often found.
Etymology and history
Paraschachnerite was first found in 1972 by E. Seeliger and A. Mücke in the type locality , the "trust-in-God" mercury mine on the Moschellandsberg near Obermoschel in Rhineland-Palatinate ( Germany ). Its name is due to the great similarity to Schachnerite .
classification
In the Strunz system , paraschachnerite is one of the metals and intermetallic compounds, a subgroup of the elements. After the 8th edition , it forms a group together with Belendorffit , lead amalgam , eugenite , gold amalgam , kolymite , luanheit , moschellandsbergite , potarite , mercury , schachnerite and weishanite . In the 9th edition , it forms a subgroup of the mercury amalgam family with eugenite, luanheit, moschellandsbergite and schachnerite.
In the systematics according to Dana it forms with lead amalgam, gold amalgam, luanheit, moschellandsbergite, eugenite, schachnerite and weishanite a subgroup (silver amalgam alloys) of the metallic elements apart from the platinum metals .
Education and Locations
Paraschachnerite is formed by the aging of moschellandsbergite under oxidizing conditions . It is associated with mercury , limonite , ankerite , argentite and cinnabarite .
In addition to the type locality, finds from the Sofia Oblast in Bulgaria , Moctezuma in Mexico , Ding and Tuwa in Russia , Kremnica in Slovakia and Sala in Sweden are known.
Crystal structure
Paraschachnerite crystallizes in the orthorhombic crystal system in the space group Cmcm or Cmc2 with the lattice parameters a = 2.916 Å , b = 5.13 Å and c = 4.83 Å as well as two formula units per unit cell .
See also
literature
- Paraschachnerite. In: Anthony et al .: Handbook of Mineralogy , 1990, 1, 101 ( PDF ).
- E. Seeliger, A. Mücke: Paraschachnerite, Ag 1.2 , Hg 0.8 , and Schachnerite, Ag 1.1 Hg 0.9 , from Landsberg near Obermoschel, Palatinate . In: New Year Mineral. Treatise 1972, 117, 1-18. Abstract in: American Mineralogist , 1973, 58, p. 347 (English, PDF ).