6 Carat Tanzanite, 18K White Gold Ring w/ Diamonds

Offered here an awesome 18K white gold ring set with an cushion cut faceted tanzanite. This ladies ring measures 8 mm in width at the top of crown and 4.4 mm in width at base of shank. The ring is size 7 and weighs 10.5 grams. The tanzanite measures 11.18 mm by 11.10 mm by 6.94 mm (approximate). The calculated weight of this gem should be approx. 6 Carats. This gem is beautiful. Graded by the gemologist appraiser as VS1 VS2 in clarity and color purple blue.
There are also 12 princess cut diamonds, 6 on each side of the Tanzanite. Those are channel set.
These are 2.61 mm x 2.61 mm each. They should be about 0.11 carats each to a total weight of approx. 1.32 carats. They are of VS1 VS2 clarity and G,H color.
Below the princess diamonds there are 18 round diamonds, 9 on each side. These measure 1.1 mm to 1.3 mm. Approx. total weight of 0.24 carats.
The ring is beautifully made and finished. The edges of diamond settings are mill grained as is the edge of the bezel holding the Tanzanite.
The side of the bezel is nicely hand engraved as is the area below the diamonds on the shank.
The two sides without the diamonds have a very nice scroll inserted in the opening. These are made with very thin flat gold wire and not simple to solder in considering how thin they are and the high heat necessary to solder them in place.
So how do you shop for a Tanzanite? As with any gem, the color is most important. Price per carat goes up with the weight of the gem.
Secondly you look at the setting: compare the weight and the gold or platinum purity used.
Small malee` diamonds that often add a nice accent to the gem are not worth more than a few hundred dollars per carat.