The Mineral carletonite
Carletonite is a rare blue mineral that is very similar to Apophyllite, and often classified as a member of the Apophyllite group. It is usually multicolored with blue and white zones, and the blue can be a very intense shade. Carletonite was named after Carleton University in Ottawa, Ontario, where this mineral was first recognized.
Chemical Formula
KNa4Ca4Si8O18(CO3)4(OH,F) · (H2O)
Color
Light to deep blue. Often color zoned with blue and white/colorless zones. May also be white with light blue splotches. Rarely pink or light orange. Solid blue crystals often display pleochroism.
Crystal System
Tetragonal
Crystal Habits
Crystals are often prismatic rectangular crystals or in groups of such crystals. Crystals terminations are usually flat but occasionally have a pyramidal angle. Also tabular, in flattened cleavage fragments, and in crude masses of distorted crystals.
Uses
Carletonite is rare collectors mineral, and is especially represented by Mont Saint Hiliaire collectors as well as thumbnail collectors.
Noteworthy Localities
Carletonite is currently found in only one locality in the world - in the Poudrette quarry in Mt. Saint Hilaire, Quebec, Canada.
Distingushing Similar Minerals
Halite - Has salty taste, occurs in different mineral environment.
Cordierite - Occurs in different environment.