EMERALD

The first emerald deposits were discovered in Egypt 3500 years ago. They were abandoned when the discovery of deposits of Colombia, operated by the Spanish in the sixteenth century. The main mining areas are now located north of Bogota, specifically Mezzo, Chive, and Conquer Gauchely. It contains the finest emeralds in the world whose value is far superior to those from Brazil, India, Pakistan or East Africa. The emerald is light green to dark green, due to a small presence of chromium and / or vanadium. It is almost always occupied impurity liquids, gas bubbles, salts and crystals of all kinds. Far from being considered defects, inclusions rather to identify the region where the emerald is derived. Forming what connoisseurs call "gardens" of an emerald, they do not diminish its value if its transparency is affected. Emeralds are very fragile stones: shock sensitive due to numerous internal cracks, they must be worn with care and caution. They are easily confused with chrome tourmaline, aconite garnet and chrome dropped. They can also be imitated by the green glass and synthetic emeralds whose production reached a level of excellence in the early '50s.

Characteristic

Crystal system: Hexagonal

Chemical Composition: Silicate of aluminum and beryllium Be3 A2 (SI6 O18)

Color: Light green to dark green, tinged with blue or yellow.

Hardness: 7.5 - 8.0 but fragile

Specific Gravity: 2.72 (0.18 -0.05)

Refractive index: 1.577 to 1.583

Dispersion: 0.014

Polychrome: Medium to pronounce (green and blue-green)

Birthstone: May