Nishapur is the oldest continuously mined turquoise mine in the world. Persian turquoise was the first to be mined as early as 7000 BC.
 
This ring is about 40 carats of the highest-grade Ajami Nishapur turquoise set in the traditional brass setting, size 11, in a traditional box. This example is seldom found outside the many shops in Mashhad Iran. It is not treated and unbacked. It is priced at $2,600. I have assigned a TG of 89 or VHG. This grade of Persian sky-blue Ajami has become very rare and more difficult to source. I purchased this ring from Shahriyar Zamansani. White spot is camera flash.