Book Review: Collector’s Guide to Herkimer Diamonds
Review of Collector’s Guide to Herkimer Diamonds, by Michael R. Walter.
Two Large Natural Pearls Reportedly from Spondylus and Trochoidea Species Mollusks
Natural pearls of unusual size and unique appearance are retrieved from the west coast of Mexico and examined in GIA’s New York lab.
Rubies from a New Deposit in Zahamena National Park, Madagascar (英語)
A field expedition from GIA Bangkok explores a new ruby deposit and collects specimens for study.
Winter 2015 G&G Publication Information
This document provides the publication information for Gems & Gemology
書籍：Towards an Art History of Medieval Rings（中世のリングの美術史に向けて）：プライベートコレクション
Towards an Art History of Medieval Rings（中世のリングの美術史に向けて）のレビュー： Sandra Hindman氏のプライベートコレクション（Ilaria Fatone氏とAngelique Laurent-di Mantova氏の協力により）
Letters: Trapiche Nomenclature
A response to the Fall 2015 G&G article on trapiche emerald from Colombia.
Trapiche Muscovite
First International Emerald Symposium
A report from the First International Emerald Symposium, held in Bogotá in October 2015.
GSA 2015 Annual Meeting
A report summarizing the annual meeting of the Geological Society of America in Baltimore.
Golden Coral Imitated by Plastic
Mexican Demantoid from New Deposits
Skarn deposits in the Veracruz state of Mexico yield new demantoid material.
Very Large Type Ib Natural Diamond
A 13.09 ct. Fancy yellow rough diamond, with C centers causing the intense color, is seen in the New York lab.
Synthetic Rock Crystal Quartz Bangle with Unusual Inclusions
A high-quality bangle with two-phase inclusions, similar to natural quartz, is found to be synthetic material.
Treated Pink Diamond with HPHT Synthetic Growth Structure
A Fancy pink type IIa diamond showing cuboctahedral growth and greenish blue phosphorescence is shown to be a natural, treated colored diamond.