The quarterly journal of the gemological institute of america

EDITORIAL
Heated Corundum, the Remarkable Winston Red, and an Extraordinary Renaissance Jewel
Duncan Pay, Editor-in-Chief
An overview of the Spring 2025 Gems & Gemology content.
Articles (4)

The 3309 cm–1 Series in Sapphire and Ruby: A Focus on FTIR Peak Position Variation
Investigates the correlations between peak positions in the 3309 cm series with trace element concentrations for ruby, metamorphic and basalt-related blue sapphire, and laboratory-grown sapphire.

A Study of the Winston Red: The Smithsonian’s New Fancy Red Diamond
Presents the first scientific and historical study conducted on the 2.33 ct Winston Red, the fifth-largest known Fancy red diamond in existence.

A Study of the Winston Red: The Smithsonian’s New Fancy Red Diamond
Archival research and gemological characterization reveal the geographic origin of two emeralds set in a pendant linked to Catherine de’ Medici, Queen of France from 1547 to 1559.

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GEM NEWS INTERNATIONAL
Global coverage of gem sources, notable new gem materials, and recent industry developments.
THE DR. EDWARD J. GÜBELIN
Most Valuable Article Awards

Laboratory-Grown Diamonds: An Update on Identification and Products Evaluated at GIA
Sally Eaton-Magaña, Matthew F. Hardman, and Shoko Odake

Observations of Oval-, Pear-, and Marquise-Shaped Diamonds: Implications for Fancy Cut Grading
Ilene M. Reinitz, Al Gilbertson, Troy Blodgett, Amanda Hawkes, James Conant, and Abhijith Prabhu

Chemical Analysis in the Gemological Laboratory: XRF and LA-ICP-MS
Ziyin Sun, Michael Jollands, and Aaron C. Palke













































































































































































































































































































































































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