The emerald it was the noblest stone of Berylle, due to its incomparable green, therefore also the term "emerald green" in the general language usage. The frequently occurring inclusions are referred to as "jardin" in the case of gemstone traders and are not measured as errors.

EMERALD:
Color: green, light green
Mos hardness: 7.5-8
Density: 2.67-2.78
Transparency: transparent to opaque
Fracture: small-muscled, uneven, brittle