Nigerian Blue Sapphires
These unheated natural blue sapphires are from the Manbilla and Jos Plateau areas in the northern part of Nigeria. The colors range from pure blue through slightly purplish blue to greenish blue; As with all sapphires, they have Hardness = 9; Refractive index = 1.79 to 1.78; Density = 3.95 to 4.02. They are balls, and the Sizes are 0.5g and bigger. Because of their shapes, they give excellent yield when cut and polished.
|Blue Sapphire||Faceted Blue Sapphire|