Diamond with Unusual Laser Manufacturing Remnant
An unusual laser manufacturing remnant, possibly once used to guide a gem cutter, was left behind in a clock-like shape.
Calcium Fluoride Coating Found on 13 "Fancy" Pink Diamonds
Recent lab examination reveals that traditional treatments such as calcium fluoride coating are still prevalent in the trade, and great care must be taken to identify them.
Spring 1991 G&G Lab Notes
This section, from the Spring 1991 issue of Gems & Gemmology, is a compilation of interesting finds from GIA’s laboratories.