EMERALD – (Specific gravity - 2.69, refractive index - 1.58)

Emeralds are probably the most hypnotic stones and come under the precious category. They are a beautiful parrot green in colour, transparent and may have some vein like inclusions in them. They are brittle, and have to be handled carefully when setting. The green colour is due to the Chromium oxide. The chemical composition consists of a Silicate of Aluminium and Beryllium. Emeralds also belong to the Beryl group. Their colours range from a very light green to a deep green. The best of Emeralds come from Columbia ( South America ) Jaipur ( India ) and Brazil.

Astrologically, the best Emeralds are those, which are Parrot green in colour, transparent and even coloured. Emeralds are also described as velvet green or grass green in colour. Emeralds should not be thickly translucent, should not have mica content, should be even coloured and there should be no black spots or white cloudy inclusions in them. Emeralds can be set in Gold or in Silver, and are usually worn on the little or middle finger. The recommended size is between two to four carats. Emerald is worn for the planet – Mercury. It's a very good stone to wear, since Mercury controls the nervous system and intellect of a person.