Emerald

History
Emeralds have been around since Egyptian and Babylonian times. One large emerald was traded in the Babylonian gem market around 4000 BC and dedicated to the goddess Venus. Cleopatra had emerald mines in Egypt by the Red Sea around 2000 BC, and it was these mines that produced most of the emeralds used in ancient jewellery.

Features
Even the finest emerald is not entirely free from flaws. The vast majority of emeralds can be seen with inclusions, and it is because of these that emeralds are somewhat fragile and brittle. Emeralds vary in color from a pale bluish green to a rich grassy green. Crystals tend to be hexagonal in shape, usually with flat ends. Emerald inclusions frequently reach the surface as microscopically fine cracks.

Treatments
As with rubies, emeralds are routinely rubbed with oil, often a cedar oil, to improve the clarity, the color, or both. Emeralds can be painted to improve their color as well, but are generally not heated, as this could damage or break the stone. Some badly flawed stones are filled with a green or transparent epoxy to improve their appearance.

Principal Deposits
Emeralds are widely found in Colombia, Brazil, Russia, South Africa, Tanzania and Zambia. They have also been discovered in Australia, the US, Pakistan and Canada.

Rarity
An emerald, by its nature, is never completely flawless. It is extremely rare to find one which has very few (or very tiny) flaws and has exceptional color, and is large enough to cut.