Chabazite

Chabazite (UK: /ˈkæbəzaɪt/)[2] is a tectosilicate mineral of the zeolite group,[3] closely related to gmelinite, with the chemical formula (Ca,K
2,Na
2,Mg)Al
2Si
4O
12•6H
2O. Recognized varieties include Chabazite-Ca, Chabazite-K, Chabazite-Na, and Chabazite-Sr, depending on the prominence of the indicated cation.

Chabazite
Salmon-pink chabazite on white heulandite
General
CategoryTectosilicate
Formula
(repeating unit)		(Ca,K
2,Na
2)
2[Al
2Si
4O
12]
2•12H
2O
Strunz classification9.GD.10
Crystal systemTrigonal
Crystal classHexagonal scalenohedral 3m
H-M symbol: (3 2/m)
Space groupR3m
Identification
ColorColorless, white, yellow, pink, red
Cleavagedistinct/good on {1011}
Fractureirregular/uneven
Mohs scale hardness4-5
Lustervitreous
Streakwhite
Diaphaneitytransparent, translucent
Specific gravity2.05 - 2.2
References[1]

Chabazite crystallizes in the triclinic crystal system with typically rhombohedral shaped crystals[2] that are pseudo-cubic. The crystals are typically twinned, and both contact twinning and penetration twinning may be observed. They may be colorless, white, orange, brown, pink, green, or yellow. The hardness ranges from 3 to 5 and the specific gravity from 2.0 to 2.2. The luster is vitreous.

It was named chabasie in 1792 by Bosc d'Antic and later changed to the current spelling.

Chabazite occurs most commonly in voids and amygdules in basaltic rocks.

Chabazite is found in India, Iceland, the Faroe Islands, the Giants Causeway in Northern Ireland, Bohemia, Italy, Germany, along the Bay of Fundy in Nova Scotia, Oregon, Arizona, and New Jersey.

Synthetic chabazite

Many different materials that are isostructural with the chabazite mineral have been synthesized in laboratories. SSZ-13 is a CHA type zeolite with an Si/Al ratio of 14. This is a composition not found in nature.

References
  1. Mineralienatlas
  2. The New Oxford Dictionary of English (1998) ISBN 0-19-861263-X - p. 300 "chabazite /'kabəzʌɪt/ noun "A colourless, pink or yellow zeolite mineral, typically occurring as rhombohedral crystals.".
  3. Chisholm, Hugh, ed. (1911). "Chabazite" . Encyclopædia Britannica. 5 (11th ed.). Cambridge University Press. p. 785.
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