Chlorastrolite

Chlorastrolite is named from Greek "chloros" - green, and "astros" - star.

Chlorastrolite is often mottled light and dark green. The most desirable pattern resembles tortoiseshell. It is widely used in jewelry items that are not subjected to heavy wear.

Chlorastrolite is the state stone of Michigan, USA.
General Information
A variety or type of:Pumpellyite Subgroup
Chemical Formula
Ca
 
2
(Mg,Fe)Al
 
2
(SiO
 
4
)(Si
 
2
O
 
7
)(OH)
 
2
· H
 
2
O)
Arthur Thomas, Gemstones (2009)
Mohs Hardness
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