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New Honorary Life Members

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

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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
Figure 1. Hand specimen with one single and two twinned staurolite crystals in a fine white mica schist host rock from Keuvy, Russia. The presentation style of specimen is typical from this location. Photo courtesy of Craig Bosel.

Staurolite and its Role as an Ornamental

13 August, 2024

The Early History of Synthetic Diamond

13 August, 2024

New Finds of Cobalt-Bearing Spinel Near Mahenge, Tazania

26 October, 2023

Gemstone Occurrences and Ancient Circular Impact-Scars: the Gemmology Tail Wags the Geology Dog

25 October, 2023

Argyle Violet Diamonds

22 November, 2022
Quartz

A Photomicrographic Compilation of Inclusions in Quartzes

20 November, 2022
Figure 2. Map showing the 255km diameter scar with the John Saul Ruby Mine, Penny Lane, Umba, Kalalani and Merelani gem deposits on its rim-zone. Unlabelled dots represent additional gem occurrences, most of which are hard rock (primary) occurrences although a few are alluvial. The more productive deposits are indicated by larger dots. Part of the rim-zone of the 1800km diameter scar is indicated by the pink band.

Gemstone Deposits of Eastern Kenya and Tanzania Controlled by Ancient Meteorite Impacts and Continental Collision – an Exploration Model

02 June, 2022