Emerald, one type of precious stones, is a variety of the mineral beryl (Be3Al2(SiO3)6). Beryl in its pure and flawless form is colorless but traces of chromium and sometimes vanadium impurities can make it green. Green beryl crystals with gemstone quality are considered as emeralds. Emeralds arenít as hard as other precious stones where on the Mohs scale, hardness of emeralds equal to 7.5-8 is lower than hardness of diamonds equal to 10 or hardness of rubies or sapphires equal to 9.0.




Back to image selection

Back to HomePage