Tri-Color-Change Holmium-Doped Synthetic CZ
A synthetic cubic zirconia shows a surprising color change combination under different light sources.
“Sango Pearl” from Japan
A study of a pink Japanese akoya cultured pearl yields information about the material’s color origin.
Atypical Bead-Cultured Pearls with Unusual Nacre Growth
Bead-cultured pearls with growth patterns within the drill holes are seen in the New York lab.
CVD Synthetic Diamond Mimicking Natural Stone
A round brilliant specimen, submitted for update service, is found to be a CVD synthetic diamond with post-growth annealing.
Diamond with Concentric Inclusions
A fancy-color diamond shows inclusions that outline growth layers.
HPHT Synthetic Diamond Melee Found In Mounted Jewelry
An HPHT synthetic diamond is found among the melee in a ring.
Book Review: Ruby & Sapphire: A Gemologist’s Guide
Review of Ruby & Sapphire: A Gemologist’s Guide
Colorful Chatoyant Glass
A devitrified glass reminiscent of Victoria Stone is seen during the Tucson gem shows.
Exhibition Review: A Modern Gem and Jewelry Collection
Chalcedony Beads Coated With Titanium Nitride
Beads in an necklace show a metallic appearance not seen in chalcedony.
New Deposits of Gem-Quality Common Opal from Michoacán, Mexico
Material from a new opal deposit in Morelia, Mexico is examined.
Raspberry-Red Garnet with Black Core
Chemical analysis is performed on the black core of a red grossular garnet crystal.
Tektite with a Large Fluid Inclusion
A large tektite found in northern Vietnam is examined in GIA’s Bangkok laboratory.
Punsiri Heat Treatment on Basalt-Related Blue Sapphire
Immersion reveals the heat treatment of a basalt-related blue sapphire.
CVD Synthetic Diamond Mimicking Natural Stone
A round brilliant specimen, submitted for update service, is found to be a CVD synthetic diamond with post-growth annealing.
Sapphire Chart Article: Suggested Reading on Sapphires and Their Inclusions
Suggested Reading on Sapphires and their Inclusions
