Emerald
The Emerald is a variety of beryllium. Its green color is the result of the incorporation of small amounts of chromium and vanadium in the the mineral's crystalline lattice.
Their hardness range from 7.5 to 8 in Mohs's scale and their specific weight varies from 2.67 to 2.78 g/cm3.
Unlike diamonds, which all seem to be the same and are valued mainly for their absolute purity, emeralds are all different and individual. Although they are judged by color, brilliance, clarity and weight, also important is the presence of inclusions or "garden". This quality reflects the geological processes that formed the gem.
The same basic characteristics of color, clarity, carat weight and cut that determine diamond values also work for emeralds. But the emphasis is on different factors.
The following are the main factors that affect the value in a Natural Emerald:
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