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The article offers world gemmology news briefs as of September 2016. The discovery of amazonite, jadeite, topazolite, demantoid, and labradorite has demonstrated the importance of systematic research of the Mexican subsoil. A team of Gemological Institute of America (GIA) field gemologists visited Tanzanian mines to collect ruby and sapphire for reference collection. A yellow sapphire from Thailand has also showed a spectrum associated with high-temperature heat treatment of blue sapphire.

Until now, the observation of three-phase inclusions in emeralds has been considered a potential indicator of Colombian origin. Nevertheless, emeralds from Afghanistan (Panjshir Valley), China (Davdar), and Zambia (Kafubu and a new deposit at Musakashi) may contain three-phase inclusions resembling those often found in specimens from Colombian deposits (Muzo, Chivor, La Pita, Coscuez, and Penas Blancas). This article presents detailed photomicrographs of samples from these localities, with a focus on their multiphase inclusions. Also investigated are spectroscopic features and trace-element data. For the gemologist studying the origin of emeralds hosting three-phase inclusions, a powerful set of tools to aid in this determination comes from the combination of detailed microscopic examination, UV-Vis-NIR and FTIR spectroscopy, and LA-ICP-MS trace-element analysis. [ABSTRACT FROM AUTHOR]

The aticle offers updates concerning gems and gemology from around the world as of December 2015. These include the discovery of demantoid garnet with giant fluid inclusion, the discovery of gem-quality grandidierite from Madagascar, and the recognition of the andradite varieties melanite, topazolite and demantoid.

The article focuses on findings from studies of several diamonds from different laboratories. Topics discussed include the baroque-shaped pearls through inductively coupled plasma?mass spectrometry (ICP-MS) and energy-dispersive X-ray fluorescence (EDXRF), the damaged nacre pearls, the natural diamonds coated with calcium fluoride (CaF2) which accounts for its pink color, a fish-like inclusion on diamond, the artificially irradiated diamond and a fancy dark orangy brown diamond.