----Lecture – 2026 AGTA GemFair Tucson DYNAMIC Seminar Series Sponsored by the American Gem Society
Attended by L. Allen Brown/All That Glitters - February 4th 2026
"There has been an increasing trade demand for colored stone origin determinations. Such a service requires comparison of the properties of the client gemstone to gem samples of known geographic origin. This presentation will take you through GIA’s scientific approach, from recovering reference samples at the mine to collecting advanced data in the laboratory. "
Presenters: Stuart Robertson, President, Gemworld International, Inc., Brecken Branstrator, Editor-in-Chief, Gemworld International, Inc.
View the Video of the Actual Lecture: The Science of Origin Determination
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