Archive for the Chrysoberyl Category
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Natural Alexandrite Gemstone
Refractive Index : 1.755 – 1.746 (+0.004 – 0.006)
Optical Characteristic : DR, biaxial positive
Specific Gravity : 3.73 (+0.02 – 0.02)
Formula : BeAl2O4
Crystal System : Orthorhombic
Variety/Species : Natural Alexandrite
Species/Group : Chrysoberyl
Birefringence : 0.008 – 0 .010
Dispersion : 0.015
Hardness : 8.5
Toughness : Excellent
Ultrasonic : Usually Safe
Steam : Usually Safe
UV Long : Inert to moderate [...]