My watch list
my.chemeurope.com  
Login  

Analcime



Analcime

General
CategoryZeolite mineral
Chemical formulaNaAlSi2O6·H2O
Identification
ColorWhite, colorless, gray, pink, greenish, yellowish
Crystal habitTypically in crystals, usually trpezohedrons, also massive to granular.
Crystal systemCubic; tetragonal, orthorhombic, or monoclinic, pseudocubic, with degree of ordering.
TwinningPolysynthetic on [001], [110]
CleavageVery poor [100]
FractureUneven to subconchoidal
Mohs Scale hardness5 - 5.5
LusterVitreous
Refractive indexn = 1.479 - 1.493
Optical PropertiesIsotropic; anomalously biaxial (-)
Streakwhite
Specific gravity2.24 - 2.29
Fusibility3.5
Other CharacteristicsWeakly piezoelectric; weakly electrostatic when rubbed or heated.
References[1]

Analcime or analcite (from the Greek analkimos - "weak") is a white, grey, or colourless tectosilicate mineral. Analcime consists of hydrated sodium aluminium silicate in cubic crystalline form. Its chemical formula is NaAlSi2O6·H2O. Minor potassium and calcium substitute for sodium. A silver bearing synthetic variety also exists (Ag-analcite).

Additional recommended knowledge

Analcime is usually classified as a zeolite mineral, but structurally and chemically it is more similar to the feldspathoids. Analcime occurs as a primary mineral in analcime basalt and other alkaline igneous rocks. It also occurs as cavity and vesicle fillings associated with prehnite, calcite, and zeolites.

Locations include the Cyclopean Islands east off Sicily and near Trentino in northern Italy; Victoria in Australia; Kerguelen Island in the Indian Ocean; in the Lake Superior copper district of Michigan, Bergen Hill, New Jersey, Golden, Colorado in the United States; and at Cape Blomidon, Nova Scotia and Mont Saint-Hilaire, Quebec in Canada; and in Iceland.

See also

References

  1. ^ http://rruff.geo.arizona.edu/doclib/hom/analcime.pdf Mineral Data Publishing
  • Hurlbut, Cornelius S.; Klein, Cornelis, 1985, Manual of Mineralogy, 20th ed., ISBN 0-471-80580-7
  • Mineral Galleries
  • Mindat.org
  • Webmineral.com
 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Analcime". 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