My watch list
my.chemeurope.com  
Login  

Margarite



Margarite is a calcium rich member of the mica group of the phyllosilicates with formula: CaAl2(Al2Si2)O10(OH)2. It forms white to pinkish or yellowish gray masses or thin laminae. It crystallizes in the monoclinic crystal system. It typically has a specific gravity of around 3 and a Mohs hardness of 4. It is translucent with perfect 010 cleavage and exhibits crystal twinning.

Additional recommended knowledge

It occurs commonly as an alteration product of corundum, andalusite and other aluminous minerals. It has been reported as forming alteration pseudomorphs of chiastolite along with muscovite and paragonite. The margarite in this occurrence forms preferentially along the dark graphite rich inclusions with the chiastolite crystals.

References

  • Deer, W.A., R.A. Howie, and J. Zussman (1963) Rock-forming minerals, v. 3, Sheet Silicates, p. 95-98.
  • Mindat with location data
  • Webmineral data
  • Mineral Data Publishing PDF
 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Margarite". A list of authors is available in Wikipedia.
Your browser is not current. Microsoft Internet Explorer 6.0 does not support some functions on Chemie.DE