The Emerald mining zones in Colombia are located basically in the ' Emerald Colombian Rectangle, an area of 250 kilometers in length by 50 of wide, within are the mines in two different departments.
The most important producers, the mines of Muzo and Coscuez, are in the department of Boyacá, about 200 kilometers to the north of Bogota and conform the "Special Esmerald Reserve". The second area of production is located to the east of the department of Cundinamarca. In this region are the mines of Chivor and Gachalá. To date, other emerald zones in Colombia have not been discovered.
The Emerald is a mineral of silicate class, categorized as a "Beryls" (BeÁI2(SiO3)6), is clear in its form of purity but often contain impurities which come from a mineral that vary in its coloration. The family of beryls includes aquamarines, blue, morganitas pink, heliodores gilded, red and green clear.
Colombian Products Guide for Importers