Aquamarine (Beryl)

Color: Light blue to blue-green

Moh’s Hardness: 7.5-8

Refractive index: 1.57-1.60

Critical Angle: 39.87°

Specific Gravity: 2.65-2.75

Cleavage: None

Fracture: Conchoidal, tough

Dispersion: Medium (.014)

Heat Sensitivity: Can be, usually not a problem

Dichroism: weak

Birefringence (double refraction): Weak (.006-.009)

Crystal Structure: Hexagonal

 

Treatments: Aquamarine is often heat treated to reduce the green/blue color and improve the blue color. It is generally safe to assume most rough has been heated.