Its a purple variety of quartz (SiO2) and owes its violet color to irradiation, impurities of iron and in some cases other transition metals, and the presence of other trace elements, which result in complex crystal lattice substitutions.The hardness of the mineral is the same as quartz, thus making it suitable for use in jewelry.
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 are highly included, so their toughness is classified as generally poor. Emerald is a cyclosilicate
Deep Blue eye clean good quality aquamarine from beryl family with hardness of 10
