Emerald
Gemstone
Emerald is a gemstone and a variety of the mineral beryl colored green by trace amounts of chromium or sometimes vanadium. Beryl has a hardness of 7.5–8 on the Mohs scale. Most emeralds have much material trapped inside during the gem's formation,... Wikipedia
Color: Green
Associated month: May
Hardness (Mohs hardness scale): 7.5 – 8
Chemical formula: Be₃Al₂SiO₆
Density: 2.67 to 2.78
Category: Beryl variety
Cleavage: Imperfect on the