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.
Ruby and Sapphire from Jegdalek, Afghanistan
This study provides detailed mining and gemmological information on the Jegdalek deposit, in east-central Afghanistan, which is hosted by elongate beds of corundum-bearing marble.
Sapphire and Garnet from Kalalani, Tanga Province, Tanzania
Located just 3 km south of the famous Umba locality, the geologically similar Kalalani area hosts deposits of gem-quality sapphire.
Tairus Hydrothermal Synthetic Sapphires Doped with Nickel and Chromium
Researchers from the Tairus joint venture have developed the technology for the hydrothermal growth of gem-quality crystals of synthetic sapphire.
Sapphires from the Andranondambo Region, Madagascar
Since 1993, large amounts of gem-quality sapphires from the Andranondambo region of southern Madagascar have entered the international gem market.
An Examination of Four Important Gems
Several famous and historical gemstones in the Smithsonian's collection are examined and reported on.
Sri Lanka: The Gem Island
An overview of the many types of gem-quality material, and its inclusions, currently found in Sri Lanka.
Abstracts; Summer 2009
This article, from the Summer 2009 issue of Gems & Gemmology, is a compilation of abstracts of important gemmology-related articles published outside of Gems & Gemmology.
The Effects of Heat Treatment on Zircon Inclusions in Madagascar Sapphires
Zircon inclusions in sapphires from Madagascar were studied to investigate the effects of heat treatment on their gemmological and spectroscopic features.