The Gemmological Association of Great Britain (Gem-A) has launched the latest issue of its flagship scientific publication, The Journal of Gemmology (Volume 39, No. 6, 2025).

Factors influencing the UV fluorescence and colour of pink-to-red spinel from Myanmar

Released digitally on June 24, this issue contains news and research from the international gemmological community, including an article providing insights into the factors influencing the UV fluorescence and colour of pink-to-red spinel from Myanmar. The authors demonstrate how the attractive pink-to-red colouration of this gem material can be bolstered by red fluorescence to visible light when an appropriate amount of Cr is present.

Opals from Madagascar, väyrynenites from Nigeria

A second feature article describes a new yellow-green variety of common opal from the Antetezambato demantoid deposit in north-western Madagascar and highlights its unusual geological context. Additional feature articles focus on exceptional gem-quality väyrynenite gemstones, reportedly from Nigeria, and inclusions in ‘petroleum quartz’ analysed using high-resolution X-ray computed micro-tomography and infrared and Raman spectroscopy.

Other columns in The Journal

In addition to the feature articles, the Gem Notes section provides numerous brief reports on diverse items of gemmological interest from around the world. Among the many items covered are a notable trapiche pink sapphire from Tajikistan; pyrope-almandine from Lao Cai Province, northern Vietnam; the successful commercial culture of abalone half-pearls in China; and updates on gem mining in the Mahenge and Landanai areas of Tanzania.

The practical and useful What’s New column highlights recent publications and online resources of interest to gemmologists, while the Learning Opportunities section contains a detailed listing of upcoming conferences and educational events to further the professional development of its readers. Finally, the New Media section compiles information on new gem- and jewellery-related books, and the Literature of Interest section lists articles published elsewhere of gemmological interest.

 

Editor-in-chief Brendan Laurs FGA says: “This issue of The Journal of Gemmology highlights gem materials from the important gem-producing countries of Myanmar, Madagascar and Nigeria, while also applying an advanced imaging technique—high-resolution X-ray computed micro-tomography—for characterising multiphase inclusions in a fascinating variety of quartz. In addition, some of the gem materials researched in this issue debuted at this year’s Tucson gem and mineral shows. The Journal continues to be an excellent source of new information valued by the gemmological community and by students, researchers and gem laboratory personnel.”

Gem-A CEO Cath Hill adds: “Our Membership publications continue to serve as a vital resource for the gemmological community, both in the UK and internationally. This issue delves into fascinating and complex topics to challenge our recent graduates, encouraging them to continually develop and nurture their skills as professional gemmologists. I want to thank all the researchers, scientists and field gemmologists who continue to contribute to this great publication and contribute towards its success in the scientific community.”

 

A leader in its field, The Journal publishes original research articles on all aspects of gemmology, including natural stones and their treatments, synthetics, and simulated gem materials. It is published quarterly in collaboration with the Swiss Gemmological Institute SSEF.

Issues published in the past two years are accessible to Gem-A Members nationally and internationally. Previous issues are freely available to anyone via The Journal’s online archive. A cumulative index covering all issues from 1947 through 2024, and numerous bibliographies covering specific subjects, can also be freely downloaded from The Journal’s website.

 

Become a subscriber to The Journal of Gemmology today!

Anyone can become an Associate Member of Gem-A and receive access to both Gem-A publications: The Journal of Gemmology (print and online) and Gems&Jewellery (online). Visit the Gem-A website to find out more.

 

 

Notes to editors

About Gem-A

The Gemmological Association of Great Britain, or Gem-A, is the world’s longest established provider of gem and jewellery education. Our Gemmology Diploma evolved from the first gem course proposed for the UK jewellery trade in 1908, and our prestigious Gemmology and Diamond Diplomas—taught in seven different languages and 26 countries around the world—are recognised globally.

Gem-A forms an international community of gem professionals and enthusiasts. We serve the interests of the gem and jewellery industries through high standards of education in our courses and our support for global gemmological research. We also provide various membership opportunities, offer high-quality gemmological instruments, and host a number of educational events throughout the year, as well as two internationally distributed publications, The Journal of Gemmology and Gems&Jewellery.

 

About The Journal of Gemmology

The Journal of Gemmology has been the official scientific journal of the Gemmological Association of Great Britain since it was incorporated in 1947. It is published quarterly in print and electronic formats. All Individual and Gold Corporate Members of Gem-A receive The Journal as part of their membership package. Institutional subscriptions are available for laboratories, libraries, museums and similar organisations. Anyone can receive The Journal by becoming a member of Gem-A.

To contact the Editor-in-Chief, please direct correspondence to Brendan M. Laurs FGA at editor@gem-a.com.

 

This scientific resource is available online now to Gem-A members to facilitate continued professional development for gemmologists.