Alexandrite
(al-eg'-zan-dryt')
1880; ger. alexandrit, from Alexander II Russian emperor
Variety of chrysoberyl used as a gemstone with a distinct green to red color change from daylight to incandescent light
Color
Distinct color change from red to green
Chemical composition
BeAL2O4
Crystal system
Orthorhombic
Hardness (Mohs scale)
8,5
Specific gravity
3,73 ±0,03
Refractive index
1,746-1,755 ±0,05
Optical character
Biaxial +