Emerald is a variety of the mineral beryl, colored green by trace amounts of chromium and vanadium. Beryl has a hardness of 7.8 – 8 on the Mohs hardness scale. Most emeralds are highly included, so their toughness is classified as generally poor.
Columbia is the world’s largest producer of emeralds. The three main emerald mines in Columbia are Muzo, Coscuez, and Chivor.
Zambia is the world’s second biggest producer. Emeralds are found all over the world in many countries. In the US, emeralds have been found in Connecticut, Montana, Nevada, North Carolina, and South Carolina.