Ruby and sapphire (usually blue, but also in every other colour) have been the most important coloured gemstones for several thousand years. Originating historically in south-east and central Asia, and more recently in eastern Africa, these coloured varieties of the mineral corundum have been much sought as gems because of their rarity, colour and durability. Gem corundum can display asterism and chatoyancy due to the presence of oriented mineral inclusions, and in some cases, a change of colour when viewed under different light sources.
Read MoreChemically pure beryl is colourless, but trace elements give rise to green, blue and pink/red colours.
Read MoreCircumnavigate the boreal reaches of the globe to explore gems from polar regions.
Read MoreCompares PL spectroscopy data of 48 emerald samples from three countries to evaluate the usefulness of the technique in geographic origin determination.
Read MoreG&G Brief presents an overview of the content of the Autumn 2015 issue of Gems & Gemology.
Read MoreThis article, from the Summer 2009 issue of Gems & Gemmology, is a compilation of abstracts of important gemmology-related articles published outside of Gems & Gemmology.
Read MoreEmeralds are again being mined in the historic district of the Ural Mountains. Physical, chemical, spectroscopic and microscopic characteristics of stones from the recent production are presented and compared with data on older samples as well as those reported in the literature.
Read MoreA treatise on the design, display, care and repair of fine gemstones.
Read MoreThis section, from the Spring 1991 issue of Gems & Gemmology, is a compilation of interesting finds from GIA’s laboratories.
Read MoreThis article, from the Spring 1991 issue of Gems & Gemmology, is a compilation of abstracts of important gemmology-related articles published outside of Gems & Gemmology.
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