Emerald is a gemstone and a variety of the mineral beryl (Be3Al2(SiO3)6) colored green by trace amounts of chromium and sometimes vanadium.
Emeralds in antiquity were mined in Egypt at locations on Mount Smaragdus since 1500 BCE, and India, and Austria since at least the 14th century CE.
[3] The Egyptian mines were exploited on an industrial scale by the Roman and Byzantine Empires, and later by Islamic conquerors.
[4] Colombia is historically an important producer of emeralds, constituting 50–95% of the world production, with the number depending on the year, source and grade.
[10] Rare "trapiche" emeralds are found in Colombia, distinguished by ray-like spokes of dark impurities.