EDITORIAL
Gems & Gemology Turns 90!
Duncan Pay, Editor-in-Chief
An overview of the Summer 2024 Gems & Gemology content.
Articles (4)
Regular Features

GEM NEWS INTERNATIONAL
Global coverage of gem sources, notable new gem materials, and recent industry developments.

Special Features

IN the SPOTLIGHT
A platinum necklace featuring 28 rare garnets won two 2023 AGTA Spectrum Awards.
THE DR. EDWARD J. GÜBELIN
Most Valuable Article Awards

Yellow Sapphire: Natural, Heat-Treated, Beryllium-Diffused, and Synthetic
John L. Emmett, Ungkhana Atikarnsakul, Jennifer Stone-Sundberg, and Supharart Sangsawong

Gemological Characterization of Montana Sapphire from the Secondary Deposits at Rock Creek, Missouri River, and Dry Cottonwood Creek
Aaron C. Palke, Nathan D. Renfro, Jeffrey R. Hapeman, and Richard B. Berg

Color Modification of Spinel by Nickel Diffusion: A New Treatment
Michael Jollands, Abadie Ludlam, Aaron C. Palke, Wim Vertriest, Shiyun Jin, Pamela Cevallos, Sarah Arden, Elina Myagkaya, Ulrika D’Haenens-Johannson, Vararut Weeramongkhonlert, and Ziyin Sun
Special Colors and Optical Effects of Oregon Sunstone: Absorption, Scattering, Pleochroism, and Color Zoning
Shiyun Jin, Aaron C. Palke, Nathan D. Renfro, and Ziyin Sun











