Colombian Emeralds as all Emerald gemstones are a variety of the mineral Beryl with traces of chromium and vanadium, which gives them their green color. The toughness of emerald gemstones is considered as poor, given that they are highly included gemstones. The formula that identifies Beryl is: (Be3Al2(SiO3)6).
Colored gemstones as emerald gemstones are graded using four simple parameters: Cut, Color, Crystal and Clarity, also known as the four Cs.
Cut is defined as the shape of the gemstone, which can be faceted as the majority of cuts, or can be cabochon cut, a rounded cut with no hard edges. The most popular faceted cuts within Emeralds are:
- Emerald cut: A squared or rectangular faceted shape.
- Cushion cut: A cut that resembles the shape of a cushion.
- Oval cut: Oval faceted shape.
Given that most emerald gemstones have surface breaking fissures, a considerable number of them are cut into cabochon rather than faceted shapes.