Lead amalgam

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Lead amalgam
General and classification
chemical formula HgPb 2
Mineral class
(and possibly department) 		Elements - metals and intermetallic compounds
System no. to Strunz
and to Dana 		1.AD.30 ( 8th edition : I / A.02)
1.1.10.1
Crystallographic Data
Crystal system tetragonal
Crystal class ; symbol 4 / mmmTemplate: crystal class / unknown crystal class
Space group I 4 / mmm (No. 139)Template: room group / 139
Lattice parameters a  = 3.55  Å ; c  = 4.55 Å
Physical Properties
Mohs hardness 1.6
Density (g / cm 3 ) 11.96
Cleavage Please complete!
colour silver-white metallic
Line color Please complete!
transparency opaque
shine metallic

Lead amalgam or Altmarkite is a very rare mineral from the mineral class of metals and intermetallic alloys . It crystallizes in the tetragonal crystal system and forms grains about 50 μm in size and silver-white in color.

Etymology and history

The mineral was first in 1981 by Chen Keqiao, Yang Huifang, Ma Letian and Peng Zhizhongin the type locality Xiaonanshan in circles Wuchuan in Inner Mongolia ( China found). It was named after its components, the elements lead and mercury .

As early as 1977, T. Kaemmel and others suggested the name Altmarkit for the lead amalgam HgPb 2 , which was proven to be "metallic solid deposits ... in underground and above-ground installations" in the natural gas deposits in Rotliegend in the Altmark .

classification

In the Strunz system , lead amalgam is classified among the elements and intermetallic compounds. In the eighth edition , it formed a group with belendorffite , eugenite , gold amalgam , kolymite , luanheit , moschellandsbergite , paraschachnerite , potarite , mercury , schachnerite and weishanite . In the ninth edition , lead amalgam can be found in the subgroup of the mercury amalgam family.

In the systematics of minerals according to Dana it forms a subgroup of the elements with other metallic elements besides the platinum group .

Education and Locations

Lead amalgam formed in a highly enriched concentrate of crushed, platinum-containing copper - nickel ore. It is associated with gersdorffite , pyrite , chalcopyrite , violarite , millerite , galena , stibnite , silver , gold , niggliite , sperrylite , iridosmium , platinum , merenskyite , kotulskite , chromite , ilmenite and magnetite . The very rare mineral has only been found in three places so far. These are the type locality in China, Moctezuma in the Mexican state of Sonora and natural gas deposits in the Altmark .

Crystal structure

Lead amalgam crystallizes in the tetragonal crystal system in the space group I 4 / mmm (space group no. 139) , the lattice parameters a = 3.55  Å and c = 3.71 Å. Template: room group / 139

See also

Individual evidence

  1. ↑ Lead amalgam in: Anthony et al .: Handbook of Mineralogy , 1990, 1, 101 ( pdf )
  2. ^ List of minerals according to Dana at webmineral.com

literature

  • T. Kaemmel, EP Müller, L. Krossner, J. Nebel, H. Unger, H. Ungethüm: Altmarkit, a new mineral (preliminary communication). - In: Zeitschrift für angewandte Geologie , Vol. 23 (1977), Akademie-Verlag Berlin, Issue 10 (October), pp. 535-536.
  • T. Kaemmel, EP Müller, L. Krossner, J. Nebel, H. Unger, H. Ungethüm: Are HgPb 2 and (Hg, Pb), formed from natural accompanying components of the natural gases of the Altmark deposits, minerals? - In: Journal for Applied Geology , Vol. 24 (1978), Akademie-Verlag Berlin, Issue 2 (February), pp. 90–96.
  • Lead amalgam in: Anthony et al .: Handbook of Mineralogy , 1990, 1, 101 ( pdf )

Web links