Emerald

Emerald is a gemstone, and a variety of the mineral beryl (Be3Al26) colored green by trace amounts of chromium and sometimes vanadium. Beryl has a hardness of 7.5–8 on the 10 point Mohs scale of mineral hardness. Most emeralds are highly included, so their toughness (resistance to breakage) is classified as generally poor.

Ruby

Topaz