Emerald specimens are the best examples of how Emeralds occur in their natural habitat. The mineral material that an Emerald crystal grows in (host rock) is called the matrix. In Colombia, Emeralds occur in pegmatic veins of white and grey calcite. Other associative minerals and rock typcially found within the same areas are black shale, quartz and pyrite. What makes a great Emerald mineral specimen? Beauty and perfection are the two most important characteristics. Along with those two characteristics, a great specimen will demonstrate the crystallography of Emerald which is a member of the hexagonal system. Emerald specimens from Colombia exhibit distinct crystal and matrix characteristics which can help identify which mining area they originated from.http://www.emeralds.com/
