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.
Black Diamonds from Marange (Zimbabwe): A Result of Natural Irradiation and Graphite Inclusions
Characterises a suite of 40 natural brown to black diamonds from this deposit so that they can be distinguished from suspected treated black diamonds.
Natural-Colour Blue, Grey and Violet Diamonds: Allure of the Deep
Summarises data collected on more than 15,000 natural blue/grey/violet diamonds examined by GIA during the last decade and examines the mechanisms that produce this colour range.
Inclusions in Natural, Synthetic and Treated Ruby
Provides a visual guide to the internal features of natural, synthetic and treated rubies.
Real-Time Microradiography of Pearls: A Comparison Between Detectors
Compares the image quality provided by real-time microradiographic imaging (RTX) units fitted with two different detectors: an image intensifier (II) and a flat panel detector (FPD).
Accurate Reporting of Key Trace Elements in Ruby and Sapphire Using Matrix-Matched Standards
Presents a group of corundum standards developed by GIA to improve the accuracy and efficiency of its laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) instruments.
Akoya Cultured Pearl Farming in Eastern Australia
Characterises the akoya cultured pearls produced on the eastern shoreline of Australia using native Pinctada imbricata fucata molluscs.
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.
The Very Deep Origin of the World’s Biggest Diamonds
Explores an exceptional family of diamonds, referred to as “CLIPPIR” (Cullinan-like, Large, Inclusion-Poor, Pure, Irregular and Resorbed), that formed in a super-deep environment.