Tanzanite
What are Tanzanite?
Tanzanite, discovered relatively recently and found only in one location on Earth, was named by Tiffany & Co. in honor of Tanzania, where it was first found in 1967. This blue-violet variety of zoisite displays different colors depending on the viewing angle, allowing cutters to create gems ranging from violetish blue to bluish violet, depending on how much weight they choose to retain from the rough crystal.
Quality Factors
Tanzanite has been the standard for blue colored stones for millennia.
Color
Deep saturated violet blue or blue violet are the most valuable tanzanite colors. Paler hues are more commonly found.
Clarity
Eye-visible inclusions decrease the value of tanzanite, particularly in lighter colored stones.
Cut
Tanzanite is available in a wide range of shapes but cushion and oval cuts are most common.
Carat Weight
Tanzanite color is less saturated in smaller sizes. Gems must be above five carats in size to have fine color.