Gemmological Characterisation of Sapphires from Yogo Gulch, Montana
A look at the mining and distinguishing characteristics of this naturally vibrant blue sapphire.
An Early Byzantine Engraved Almandine from the Garibpet Deposit, Telangana State, India: Evidence for Garnet Trade Along the Ancient Maritime Silk Road
Analyses the chemical composition and inclusion characteristics of this ancient artefact.
Gem Virtuosos: The Drehers and Their Extraordinary Carvings
A look at the artistic heritage of the Drehers, an influential family of gem carvers in Idar-Oberstein, Germany.
Synthetic Star Sapphires and Rubies Produced by Wiede’s Carbidwerk, Freyung, Germany
Details the process used by Wiede’s Carbidwerk to produce star synthetic corundum from the mid-1950s until the 1970s.
Observations on HPHT-Grown Synthetic Diamonds: A Review
Summarises statistical data and distinctive features of several thousand gem-quality HPHT synthetic diamonds examined by GIA from 2007 through 2016.
Japanese Jadeite: History, Characteristics and Comparison with Other Sources
Examines the sources, colour, texture and chemical composition of jadeite from Japanese deposits.
Fabergé Cossack Figures Created from Russian Gemstones
Hardstone figures of two Russian imperial bodyguards, commissioned in 1912 by Nicholas II, demonstrate the House of Fabergé’s meticulous detail and craftsmanship.
Jaipur, India: The Global Gem and Jewellery Power of the Pink City
Examines Jaipur’s role as a coloured stone cutting and jewellery manufacturing centre, with profiles of 17 companies and their factory, trading and retail operations.
Beryllium Diffusion of Ruby and Sapphire
The heat treatment of corundum involving lattice diffusion of beryllium (Be) at temperatures over 1800°C has become a major issue in the gem trade.
G. Robert Crowningshield: A Legendary Gemmologist
G. Robert (Bob) Crowningshield has made many significant contributions to the study of gems and the science of gemmology.