The Muzo mine comprises several
emerald-bearing areas. The main area, the
Tequendama quarry, has been mined for more than 300 years.
The
emerald crystals usually occur in small cavities and vugs, in bulges of calcite veins where the veinlets intersect, and in the vein selvages in vugs ("pockets") in the country rocks, which are connected with the veins by thin carbonate or albite veinlets. The
emerald is initially associated with coarse-grained dolomite and parisite.
Emerald crystals are also disseminated in the black shales near calcite veins and contain numerous relict particles of the coaly material, which supports a metasomatic origin.
Emeralds from the veins and "pockets" in the shales are represented by prismatic often short-columnar crystals to 3 cm long. Larger
emeralds, some as much as 15 cm in length, are occasionally recovered. Some are of very high gem quality and have established worldwide recognition for the Colombian
emeralds (example is Devonshire
emerald - 1384 carats).
The
emerald colour varies from light green to bright and deep green, it depends on the content of chromophore admixtures. Muzo emeralds have a yellowish tint. Solid inclusions in
emerald are very fine particles of carbonaceous matter.
Ref: E.Ya. Kievlenko (2003) Geology of gems, pp. 99, 100, 101
Gemstone List
Gem list contains entries from all listed localities in region.
Gemstones from Muzo Municipality, Western Boyacá Province, Boyacá Department, Colombia by Colour
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Localities in this Region
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