Iridescent Tabasco Geode
Tabasco geodes are a small geode variety named for the area where they are mined in the Mexican state of Zacatecas, near the city of Tabasco.
Quarterly Crystal: Dioptase in and on Quartz
Crystals of transparent colorless rock crystal quartz play host to a wide variety of mineral inclusions, some of which are highly attractive.
Plume Agate from Iran
Two varieties of colorful plume agates, characterized by inclusions resembling clouds of smoke, are sourced from Iran.
Euhedral Phantom Sapphire in Sapphire
A phantom sapphire crystal within a host sapphire crystal was recently examined at GIA’s Carlsbad laboratory.
Summer 2019 G&G Publication Information
This document provides the publication information for Gems & Gemology
Color-Change Spessartine Garnet: A First Report
The Carlsbad laboratory encounters a unique spessartine garnet that displays a strong color change from dark green to dark red.
Dyed Serpentine Imitating Sugilite
Advanced testing confirms dyed material as serpentine, rather than the sugilite it was meant to imitate.
Faceted Milarite
A light yellow 2.07 ct oval brilliant is the first faceted milarite examined by the Carlsbad laboratory.
Exsolved Particles with Natural Appearance Within Flux-Grown Pink Synthetic Sapphire
Flux-grown pink synthetic sapphire displays a natural-looking inclusion scene.
Resin-Coated and Clarity-Enhanced Aquamarine Pendant
Careful examination by the Carlsbad laboratory identifies both coating and clarity enhancement of an aquamarine pendant.
Separation of Kornerupine and Prismatine
GIA’s laboratories are now using LA-ICP-MS to separate kornerupine from prismatine based on boron concentrations.
Spurrite
Recently, the Carlsbad laboratory identified a 19.68 ct gray-purple spurrite with the help of advanced testing.
Intergrown Emerald Specimen from Chivor
An emerald specimen from Chivor hosts a large, well-formed emerald inclusion.
Glass-Filled Polki-Cut CVD Synthetic Diamonds
India’s Gem Testing Laboratory (GJEPC) encounters glass-filled CVD synthetic diamond polkis for the first time.
Nathan Renfro Wins Royal Microscopical Society Award
Regular G&G contributor receives award for his work in the field of gemology.
Ornamental Jadeites from the Levoketchpel Deposit in the Polar Urals of Russia
Gemological and trace element chemical characteristics of ornamental jadeites from the Levoketchpel deposit in Russia are compared with other sources.
Rubies from Rock Creek, Montana
A study on American ruby and sapphire from Rock Creek, Montana, unveils a few geochemical mysteries.
Book Review: Farah Khan: A Bejeweled Life
Review of Farah Khan: A Bejeweled Life by Paola De Luca.
