Andalusite

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Andalusite
Chemical composition Al2SiO5
Crystal system Orthorhombic
Habit Prismatic
Cleavage Distinct
Fracture Sub-conchoidal
Hardness 7.5
Optic nature Biaxial -
Refractive index 1.63-1.64
Birefringence 0.010
Dispersion Low, 0.016
Specific gravity 3.18
Lustre Vitreous
Pleochroism Very strong

Andalusite
Photo courtesy of Distinction Jewelry
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Location: Sierra Albarrana, Cordoba, Spain

Andalusite is a little known and much under appreciated gem. It is highly pleochroic, meaning that it appears to be different colors depending upon from which direction the stone is viewed. The most common colors are a bronzed red coupled with a golden green. Although it is often refereed to as "poor man's alexandrite" because of the tone of it's pleochroic colors, it actually does NOT have the ability to change colors like alexandrite does. Andalusite is named after Andalusia, the province of Spain where it was first discovered. It is said to stimulate the memory and recollection. Not only recent memory, but it is actually attributed with the ability to make one able to remember their past lives.