CANASITE: Bur’atskaja, Urals, Siberia, USSR (~2 inches across)
The material usually seen on the market as “canasite” is purplish in color. It is frequently confused with another purplish material, a member of the serpentine family known as stichtite. However, stichtite occurs in elongated fibers that have a kind of lustrous sheen, almost asbestiform, whereas canasite is granular. Recent research seems to indicate that, in fact, the material being called “canasite” has not canasite in it but is a new, distinct species.
Canasite Value
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Canasite Information
| Data | Value |
| Name | Canasite |
| Crystallography | Monoclinic. Occurs in tiny grains, usually twinned. |
| Colors | Greenish yellow. |
| Luster | Vitreous. |
| Hardness | 5-6 |
| Density | 2.707 |
| Birefringence | 0.009 |
| Cleavage | Perfect 1 direction, good 1 direction. Brittle; grinds to felt like powder. |
| Stone Sizes | Massive blocks up to several inches have been found. Material is cut as cabochons and decorative objects. |
| Spectral | Not diagnostic. |
| Formula | (Na,K)5(Ca, Mn, Mg)4(Si2O5)5(OH, F)3 |
OPTICS: a= 1.534; β 1.538; γ = 1.543
Biaxial (-), 2V, ~53°
OCCURRENCE: Occurs in pegmatite in the Khibina Tundra, USSR
COMMENTS: The material usually seen on the market as “canasite” is purplish in color. It is frequently confused with another purplish material, a member of the serpentine family known as stichtite. However, stichtite occurs in elongated fibers that have a kind of lustrous sheen, almost asbestiform, whereas canasite is granular. Recent research seems to indicate that, in fact, the material being called “canasite” has not canasite in it but is a new, distinct species.
NAME: From the composition: Ca, Na, and Si.
