Imitation Rainbow Moonstone Assemblage
Examination of an imitation rainbow moonstone assemblage containing plastic-coated gypsum.
Inside De Beers’ Lightbox Diamonds
GIA researcher analyzes and confirms that De Beers’ Lightbox diamonds are grown using the chemical vapor deposition process.
Solution-Generated Pink Color Surrounding Growth Tubes and Cracks in Blue to Blue-Green Copper-Bearing Tourmalines from Mozambique
Several transparent, faceted, blue to blue-green copper-bearing tourmalines containing growth tubes and cracks surrounded by sleeves of pink color were examined for this report.
Characterization of Peridot from Sardinia, Italy
Gem-quality peridot is occasionally found as mantle xenoliths within basalts near Pozzomaggiore.
Identification of Extraterrestrial Peridot by Trace Elements
Twenty-six peridot samples from the Esquel pallasite meteorite and 27 samples from 10 terrestrial sources were studied by laser ablation.
New Deposit of Black Opal from Ethiopia
The Stayish mine in Ethiopia’s Wollo province has been producing black opal since 2013.
Purple Pyrope-Almandine Garnet From Mozambique
Analysis of attractive purple garnets from a new deposit in central Mozambique.
Composite Amber with an Unusual Structure
This 9.12 gram amber composite featured a combination of natural and imitation amber, accompanied by natural and artificial insect inclusions.
Manufactured Gold-in-Quartz Jewelry
Manufactured gold-in-quartz jewelry was examined in the Carlsbad lab.
Chart: Inclusions in Natural, Synthetic, and Treated Diamond
Provides a visual guide to the internal features of natural, synthetic, and treated diamonds.