Chrysoberyl and Alexandrite from the Pegmatite Districts of Minas Gerais, Brazil
Mining fine cat's-eye chrysoberyl and alexandrite in Brazil.
An Update on Color in Gems. Part 2: Colors Involving Multiple Atoms and Color Centers
This is the second part in a three-part series on the origin of color in gem materials.
The Seven Types of Yellow Sapphire and Their Stability to Light
The authors determined that there are actually seven types of
The History and Gemology of Queen Conch "Pearls"
This article reviews the history of the conch "pearl," discusses S. gigas and its fisheries, and examines the gemological properties and other characteristics of this attractive material.
The Gemological Properties of the De Beers Gem-Quality Synthetic Diamonds
Examination of a group of 14 brownish yellow, yellow, and greenish yellow synthetic diamonds reveals distinctive gemological properties.
An Update on Color in Gems. Part 1: Introduction and Colors Caused by Dispersed Metal Ions
This three-part series of articles reviews our current understanding of gemstone coloration.
The Occurrence and Gemological Properties of Wessels Mine Sugilite
An examination of the two types of sugilite found at the Wessels mine in South Africa.
Gemstone Durability: Design to Display
A treatise on the design, display, care and repair of fine gemstones.
A New Gem Material from Greenland: Iridescent Orthoamphibole
A study of iridescent orthoamphiboles marketed as Nuummite.
Contemporary Intarsia: The Medvedev Approach to Gem Inlay
The techniques of this precision inlay style are explained.
Art Nouveau: Jewels and Jewelers
This article discusses the origins of Art Nouveau and outlines the distinctive interpretations and contributions made by significant Art Nouveau jewelers.
The Gemological Properties of the Sumitomo Gem-Quality Synthetic Yellow Diamonds
Sumitomo Electric Industries is producing gem-quality synthetic yellow diamonds in deep yellow single crystals in sizes up to 2 ct.
Fall 1986 G&G Lab Notes
This section, from the Fall 1986 issue of Gems & Gemology, is a compilation of interesting finds from GIA's laboratories.
Carbon Dioxide Fluid Inclusions as Proof of Natural-Colored Corundum
An important clue in identifying natural-colored corundum is the presence of carbon dioxide fluid inclusions.
A Simple Procedure to Separate Natural from Synthetic Amethyst on the Basis of Twinning
Where there are no inclusions or color zoning, the presence of Brazil twinning in the natural amethyst will usually make the distinction.
Summer 1986 G&G Lab Notes
This section, from the Summer 1986 issue of Gems & Gemology, is a compilation of interesting finds from GIA’s laboratories.
An Examination of Four Important Gems
Several famous and historical gemstones in the Smithsonian's collection are examined and reported on.
The Elahera Gem Field in Central Sri Lanka
The Elahera gem field currently provides approximately 35% of the gemstones exported from Sri Lanka.
コスクエス鉱山：コロンビア産エメラルドの主要原産地 (英語)
The Coscuez mine, one of a number in Colombia, is rapidly gaining significance as a major source of fine emeralds.
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