The stones are close to 500 million years old, according to the mine’s site. The site also offers to turn the newly discovered finds into jewelry on site. Prices vary with three-day passes ...
Figure 1. Pleochroism in a 15 ct tanzanite, as seen with the unaided eye through the crown and the pavilion sides and ends. Photo by Wimon Manorotkul. In describing colored gemstones, the major ...