Carletonite
Image: Robert M. Lavinsky (CC BY-SA 3.0)
Mineral NameCarletonite
Chemical FormulaKNa₄Ca₄Si₈O₁₈(CO₃)₄(F,OH)·H₂O
Mohs Hardness4.5
Crystal Systemtetragonal
Lustervitreous
Streak Colorwhite
Cleavageperfect on {001}
Fractureuneven
Specific Gravity2.5
Colorsblue, violet-blue, light blue, white, colorless
Transparencytransparent
Type LocalityPoudrette quarry, Mont Saint-Hilaire, Rouville RCM, Montérégie, Quebec, Canada
Mineral GroupSilicates
Usescollector
Associated Mineralsaegirine, analcime, calcite, eudialyte, natrolite, serandite, sodalite, villiaumite
Rarityrare
Description
This specimen displays blocky, tabular crystals of a striking violet-blue color, often intergrown with other minerals or within a lighter matrix.
Geological Context
Carletonite is a rare mineral found in nepheline syenite pegmatites and miarolitic cavities within alkaline intrusive complexes, typically forming under late-stage hydrothermal conditions.
