Carletonite - Encyclopedia
Class : Silicates
Subclass : Phyllosilicates
Crystal system : Tetragonal
Chemistry : KNa4Ca4Si8O18(CO3)4(OH,F) H2O
Rarity : Very rare
Carletonite is an extremely rare complex silicate, whose structure is similar to that of apophyllite and also contains CO3 groups. It owes its name to the University of Carleton (Canada) where it was studied. It is a mineral known in enclaves metamorphosed into hornfels and marbles within a nepheline syenite of a gabbro-syenite complex. It is usually massive, but can produce prismatic crystals up to 6 cm. It is frequently zoned, pale blue to dark blue, sometimes colorless. It is an exceptionally cut mineral as a gemstone.
Main photo : Carletonite from Poudrette Quarry, Mont Saint-Hilaire Quebec, Canada © Nadya Georgieva
Carletonite in the World
Twinning
No twin known for this mineral species.
Fakes and treatments
No fake identified for this mineral species.
Hardness : 4 to 4.5
Density : 2.45
Fracture : Conchoidal
Streak : White
TP : Translucent to transparent
RI : 1.517 to 1.521
Birefringence : 0.004
Optical character : Uniaxial -
Pleochroism : Low
Fluorescence : None
Solubility : -
Magnetism : None
Radioactivity : None