Wikipedia
Muzo
Muzo is a town and municipality in Boyacá Department, Colombia, part of the subregion of the Western Boyacá Province. It is widely known for the nearby emerald mines containing perhaps the world's highest quality gems of this type. The Muzo mines are situated in the western foothills of the eastern range of the Colombian Andes, about 96 km northeast of Bogotá. The Devonshire, one of the world's most famous uncut emeralds, is from the Muzo mines. It is a 1383.95 carat (276.79 g) emerald and was a gift to the 6th Duke of Devonshire by Emperor Dom Pedro I of Brazil in 1831.
The US National Museum Division of Mineralogy and Petrology carried out a study of the mines in 1916.