The quarterly journal of the gemological institute of america
EDITORIAL
A Review of HPHT Synthetic Diamonds Grown for Jewelry Use
Duncan Pay, Editor-in-Chief
An overview of the Fall 2017 Gems & Gemology content.
Articles (6)
Saltwater Pearls from the Pre- to Early Columbian Era: A Gemological and Radiocarbon Dating Study
Examines 85 saltwater natural pearls, reportedly harvested from the Caribbean islands off the coast of Venezuela during the early 16th century, to determine their age.
Observations on HPHT-Grown Synthetic Diamonds: A Review
Summarizes statistical data and distinctive features of several thousand gem-quality HPHT synthetic diamonds examined by GIA from 2007 through 2016.
Photoluminescence Spectra of Emeralds from Colombia, Afghanistan, and Zambia
Compares PL spectroscopy data of 48 emerald samples from three countries to evaluate the usefulness of the technique in geographic origin determination.
Synthetic Star Sapphires and Rubies Produced by Wiede’S Carbidwerk, Freyung, Germany
Details the process used by Wiede’s Carbidwerk to produce star synthetic corundum from the mid-1950s through the 1970s.
True Colors of “Dalmatian Jasper”
Discusses the mineralogical composition and provenance of this spotted decorative gemstone.
Colombian Emerald Industry: Winds of Change
A firsthand look at Colombia’s emerald mines and the cutting and trading industry in Bogotá.
Regular Features
GEM NEWS INTERNATIONAL
Global coverage of gem sources, notable new gem materials, and recent industry developments.
2017
G&G CHALLENGE WINNERS
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Congratulations to the readers who earned a perfect score on this year's Challenge quiz.
