GIA field gemologists Andrew Lucas (left) and Vincent Pardieu (right) and Gems & Gemology technical editor Tao Hsu (middle) visited an underground sapphire mine in Rubyvale, Queensland. Photo by Victoria Raynaud/GIA.
The Australian sapphire industry modified mining processing techniques for other materials, such as tin, to create systems like this one at Inverell. Photo by Andrew Lucas/GIA.
Some of these sapphire crystals still have host rock attached, which is fairly rare in Australia. Photo by Vincent Pardieu/GIA.
Figure 1. The “Rainbow Over Montana” bracelet contains 76.83 carats of Montana sapphire (71.42 carats rough and 5.41 carats faceted). The ring from the same collection contains 11.57 carats of rough and 1.12 carats of faceted Montana sapphires. Photo by Robert Weldon/GIA; courtesy of Paula Crevoshay.