For more than a century, the Four Peaks mine in Maricopa County, Arizona, has produced gem-quality amethyst from crystal-lined or crystal-filled cavities and fractures in a brecciated quartzite host rock.

Northern Vietnam began producing significant quantities of rubies and fancy sapphires in the late 1980s.

Examination of a 0.40 ct near-colorless round brilliant diamond with a large inclusion resembling a dumbbell

Since late 2007, rubies and sapphires have been mined by hand methods from both eluvial and primary deposits at Winza in central Tanzania.

Gem-quality rubies and pink to purple sapphires are being recovered from the Luc Yen and Quy Chau mining regions of Vietnam.

Uniquely saturated examples of the collector stone were on display at GJX.