GIA’s renowned journal, Gems & Gemology, marks a significant milestone with its 60th volume. This issue, the second of 2024 and released last summer, offers a wealth of valuable content and updates for gemology professionals. Topics range from synthetic diamonds and Chinese cassiterite to Vietnamese anorthoclase, Australian emeralds and tourmalines, and Valentina Fetisova’s stunning painted labradorites.
The article “Gem-Quality Anorthoclase Feldspar from Southeast Vietnam” by Le Ngoc Nang, Pham Minh Tien, Pham Minh and Pham Trung Hieu discusses gem-quality anorthoclase found in southeastern Vietnam. This mineral, which occurs as megacrystals in basalt, ranges from transparent to translucent, with colors ranging from brownish gray to yellow and nearly colorless. The article describes the gemological and spectroscopic methods used to confirm the gem’s identity, including X-ray diffraction and fluorescence techniques. The results show that Vietnamese anorthoclase has significant commercial potential due to its abundance and quality, making it ideal for faceting and cabochon cutting.
Sally Eaton-Magaña, Matthew F. Hardman, and Shoko Odake contribute the article “Laboratory-Grown Diamonds: An Update on Identification and Products Evaluated at GIA”, which traces the evolution of lab-grown diamonds over the past two decades. The GIA has observed a sharp increase in the quantity, quality, and size of these diamonds, making them increasingly viable for large-scale marketing. The study summarizes the two primary growth methods: HPHT and CVD. Currently, CVD diamonds dominate the market, often enhanced with HPHT treatments to improve their color. While production capacity has stabilized in recent years, future growth is expected, especially for large, colorless diamonds.
Also in this issue, readers can enjoy an interview with Robert Weldon, Orasa Weldon and Nathan Renfro, entitled “Dance of Light and Color: Painted Labradorite”, which explores the artistic journey of Valentina Fetisova. A former professional dancer, Fetisova turned to painting labradorite, using the stone’s natural labradorescence to create unique works of art. The article reveals her meticulous artistic process, which includes sanding, layering paint, and manipulating light to bring out the stone’s unique beauty. A gallery of her work is also included at the end of the article.
Wim Vertriest, Suwasan Wongchacree and Polthep Sakpanich’s article “New Emerald Production from the Curlew Mine, Western Australia” examines the characteristics and production of Australian emeralds, specifically from the Curlew Mine. Although Australian emeralds have been known for over a century, their poor clarity and less intense color have limited their success on the world market. After a long period of inactivity, mining resumed in 2023, allowing GIA to analyze 69 emeralds from this recent production.
