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New Honorary Life Members

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Featured news

AG Article: Women’s work in the gemstone supply chain: Africa, India and Thailand

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The Umba Sapphire Story: 1960 to 2024

20 July, 2026

Characterization of Sri Lankan Geuda Sapphires which have Undergone Different Heat Treatments

20 July, 2026
Figure 10. Authors Robin Hansen (left), Léonie Rennie (centre) and François Farges (right) holding MNHN 96.135, the Moissan model of The Sergio. Photo courtesy of Kaylee Hansen.

The Sergio: The Life and Times of the World’s Largest Carbonado Part 2

03 February, 2026
Figure 2. Petrographic section of Carrara marble from the Apennine Mountains, Italy. Note the well-formed equigranular calcite crystals displaying high birefringence and twinning lamellae. Crossed polarized view FOV: 2mm. Photo courtesy of the author.

Calcite – An Unlikely Gemstone with a Legacy

03 February, 2026

The Sergio: An Exploration of the World’s Largest Carbonado – Part 1

04 May, 2025
Figure 1. Green tourmaline from Zambia which is highly transparent and mostly free of inclusions. Left: 44.60ct crystal; right: 9.62ct faceted tourmaline which were part of the study sample.

Green Tourmaline from the Hofmeyr Mine, Eastern Zambia

04 May, 2025
Figure 1. A carving of “lemon ‘n’ lime” chrysoprase from the open cut deposit at Marshall Pool, Western Australia, showing gradation of colour typical of the best material. Size: 60mm x 40mm.

“Lemon ‘n’ Lime” Chrysoprase: A Brief Overview of Chrysoprase from Marshall Pool, Western Australia

04 May, 2025
Figure 11. A polished face of precious boulder opal from the Arch Mine. (Photo A. Kent).

Queensland Precious Opal Deposits and Associated Critical Mineral Enrichment within Silicified Palaeochannels

08 February, 2025
Figure 1. The necklace showing the range of collet-set gemstones interspersed with gold chain.

A Story in a Gemstone Necklace

08 February, 2025