Chabazite-Ca
Image: Modris Baum (Public domain)
Mineral NameChabazite-Ca
Chemical FormulaCaAl2Si4O12 · 6H2O
Mohs Hardness4.5
Crystal Systemtrigonal
Lustervitreous
Streak Colorwhite
Cleavagedistinct on {1011}
Fractureuneven to conchoidal
Specific Gravity2.1
Colorsyellowish-brown, white, colorless, pink, red, brown
Transparencytransparent to translucent
Type LocalityPoudrette quarry, Mont Saint-Hilaire, Rouville RCM, Montérégie, Québec, Canada
Mineral GroupSilicates (Zeolite Group)
Usescollector, scientific research
Associated Mineralsother zeolites, apophyllite, calcite, quartz, nepheline, sodalite
Rarityuncommon
Description
The image displays small, yellowish-brown rosettes of chabazite-Ca crystals, resembling honeycomb, nestled on a darker matrix. These well-formed crystals exhibit a vitreous luster.
Geological Context
Chabazite-Ca is a zeolite mineral that typically forms in the vesicles and cavities of basaltic volcanic rocks, as well as in some alkaline igneous intrusions like Mont Saint-Hilaire. It crystallizes from the alteration of volcanic glass or other primary minerals by low-temperature hydrothermal fluids.
