The name emerald derives from Greek “smaragdos” – or green stone. It is the most precious stone in the beryl group. Its green is incomparable, and is therefore called “emerald green”. Emerald is highly valued for its deep bright green colour, transparency and high hardness. Along with diamond and ruby, it is one of the most precious gemstones among all since ancient times.
The crystals are usually small with average length of 2 – 5 cm and width of 1 – 1.5 cm. Larger crystals are usually semi-transparent to opaque. Flawless faceted emeralds exceeding 5 carats are rather rare.