Emerald is a gemstone and a variety of the mineral beryl (Be3Al2(SiO3)6) colored green by trace amounts of chromium and sometimes vanadium
Beryl has a hardness of 7.5–8 on the Mohs hardness scale, making it harder than Quartz. Most emeralds are highly included, so their toughness (resistance to breakage) is classified as generally poor. Emerald is a cyclosilicate.
As a healing crystal, Emerald is associated with the heart chakra and brings vitality and freshness to relationships, as well as having the ability to help you heal hurt emotions.
This crystal is also known to simulate the mind.