Summer 2025 G&G Available Now

Erica Zaidman

August 29, 2025

The summer issue of Gems & Gemology has much in store, including the intriguing world of phenomenal gems. Along with G&G’s regular sections, this installment features the return of the Colored Stones Unearthed column and profiles an award-winning gem cutter.

Structures Behind the Spectacle: A Review of Optical Effects in Phenomenal Gemstones and Their Underlying Nanotextures

The issue’s only feature article is packed with valuable information for the practicing gemologist. GIA authors Dr. Shiyun Jin, Nathan Renfro, Dr. Aaron Palke, and Dr. James Shigley provide a comprehensive review of the special optical effects in gemstones, including opalescence, chatoyancy, asterism, schiller, and iridescence, and investigate the optical processes and submicron textures that cause these phenomena.

Lab Notes

GIA’s global laboratory staff present their latest findings in the Lab Notes section, including a CVD-grown diamond with an unusual cause of green color, diamonds submitted with counterfeit inscriptions, and a pezzottaite with multiple cat’s-eyes.

Micro-World

The Micro-World section, dedicated to the inner world of gemstones, features a rutile star in quartz, a “sugar plum” inclusion in sapphire, a unique phantom crystal in diamond, and more.

Colored Stones Unearthed

The Colored Stones Unearthed column returns in this issue, covering the geology, mineralogy, and formation of granitic-composition pegmatites and summarizing their worldwide occurrences.

Gem News International

The GNI section contains various reports from contributors worldwide, such as a nacre classification update to the GIA 7 Pearl Value Factors, new väyrynenite production from Nigeria, and a multilayered laboratory-grown diamond.

In the Spotlight

Lastly, we highlight the incredible artistry and extraordinary life of gem cutter Ben Kho, from his perilous beginnings in Cambodia to a fresh start and successful career in the United States.