De Beers near Colorless-to-Blue Experimental Gem-Quality Synthetic Diamonds
A New Gem Beryl Locality: Luumäki, Finland
Strongly etched prismatic crystals of yellow, green, and pale blue gem beryl have been quarried from a pegmatite dike in Luumäki, Finland.
Diamond Sources and Production: Past, Present, and Future
Diamond production’s future appears to belong less to Africa and more to Australia, Canada, and the Russian Federation, according to this overview of geologic trends in the industry.
Methods for Determining Gold Content of Jewelry Metals
Verifying the gold content of karat-gold jewelry is a problem for the entire industry.
在缅甸摩谷矿区开采的红宝石和蓝宝石现状 (英语)
Burma, now named Myanmar, has for centuries been considered the world's preeminent source of fine rubies.
Identification of Bleached and Polymer-Impregnated Jadeite
The "bleaching" treatment of jadeite jade has become prevalent in higher- as well as lower-quality material.
Dyed Natural Corundum as a Ruby Imitation
The gemological properties of a new ruby imitation, produced by dyeing natural colorless to pale-colored corundum, are described.
Peridot as an Interplanetary Gemstone
The stony-iron meteorites known as pallasites are famed for the areas of yellowish green olivines they contain.
Curves and Optics in Nontraditional Gemstone Cutting
Sunstone Labradorite from the Ponderosa Mine, Oregon
The Ponderosa mine is now producing commercial quantities of the gem-quality labradorite feldspar known as sunstone.
越南红宝石与彩色蓝宝石 (英语)
Gem-quality rubies and pink to purple sapphires are being recovered from the Luc Yen and Quy Chau mining regions of Vietnam.
Spring 1991 G&G Lab Notes
Age, Origin, and Emplacement of Diamonds: Scientific Advances in the Last Decade
Diagnostic Features and Heat Treatment of Kashmir Sapphires
Today, only by combining different gemological tests with years of practical experience, can a conclusive determination of the origin of a sapphire be made.
An Investigation of a Suite of Black Diamond Jewelry
富有传奇色彩的德雷斯顿绿钻 (英语)
In addition to its rich history, the Dresden Green offers an opportunity to gain information about how to distinguish natural from laboratory-irradiated green diamonds.
Majorica Imitation Pearls
This article discusses the history of the Majorica imitation pearl, the manufacturing and marketing processes, and the separation of the Majorica product from its cultured counterparts.
Gem-Quality Cuprian-Elbaite Tourmalines from São José Da Batalha, Paraíba, Brazil
Unusually vivid tourmalines from the state of Paraiba, in north eastern Brazil, have attracted great interest since they first appeared on the international gem market in 1989.

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