Poster abstracts on “Diamond Identification” from GIA’s 2018 International Gemological Symposium.
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.
Carbonado Diamond: A Review of Properties and Origin
Presents a detailed examination of about 800 samples of carbonado diamond from Brazil and the Central African Republic, including possible models for its genesis.
An Update on Tourmaline from Luc Yen, Vietnam
Reviews the characteristics of tourmaline from pegmatites in the Luc Yen district of northern Vietnam.
Japanese Jadeite: History, Characteristics, and Comparison with Other Sources
Examines the sources, color, texture, and chemical composition of jadeite from Japanese deposits.
Causes of Iridescence in Natural Quartz
Describes the occurrence of iridescence, and the role of differential etching, in quartz crystals from India’s Jalgaon District.
Largest Blue HPHT Synthetic Diamond
Analysis of a 5.03 ct HPHT-grown blue synthetic diamond, the largest ever examined by GIA.
An Introduction to Photoluminescence Spectroscopy for Diamond and Its Applications in Gemology
Presents the underlying physics and methodology of this analytical technique, which has become an essential tool in identifying treated and synthetic diamonds.
Colombian Trapiche Emeralds: Recent Advances in Understanding Their Formation
Proposes a model for trapiche emerald formation based on petrographic, spectroscopic, and chemical examination.