Before the arrival of the Spanish, the precious green gemstones were unearthed by the native people of today's Boyacá province. The emeralds were of major significance for the indigenous people and were used as adornments but also in religious rituals and ceremonies. During the 16th century, after many bloody conflicts with the native people, the Spanish took over the emerald mines and began exporting large quantities to quench the thirst of European royalty but also Indian Moghul rulers for the beautiful gemstone of eternal springtime. Today, most mines are leased to private companies while others are in private hands entirely.
Emeralds from the picturesque valleys and hills of the Colombian mining areas are often said to be of a deep bluish-green ranging to an almost velvety, grassy yellowish-green colour. They are known for their unusual combination of good size, attractive colour and above average clarity. One reason for the extraordinary qualities that are associated with Colombian emeralds lies in the way they have formed many million years ago. Other than most emeralds from other locations around the world, the green gems from Colombia were not created by metamorphic processes in igneous rock but by hydrothermal processes in sedimentary rock. Colombian emeralds regularly command record prices per carat at auction and the majority of the most expensive emeralds ever sold were unearthed among the lush green forests of Colombia.
A few years ago it was believed that a specific inclusion in an emerald, the so called three-phase-inclusion, was a very strong if not even definite indication for the Colombian origin of the gemstone. Three-phase-inclusions are inclusions in gemstones, particularly in emeralds, that consist of a solid, a liquid and a gas bubble. Recent discoveries of emeralds from Zambia, Afghanistan and China with very similar inclusions, however, have rendered this easy way of identifying Colombian emeralds moot. Only a combination of a broad range of microscopic, spectroscopic and chemical testing methods may yield results that allow gemmologists to say with confidence that an emerald actually comes from this most coveted of emerald origins, Colombia.