Heliodor and Aquamarine with Surface Etching
Hexagonal etch features are observed on the prismatic faces of heliodor and aquamarine crystals.
Large Natural Diamonds with Asteriated Cloud Inclusions
Two natural diamonds containing cloud inclusions that resemble stars are examined in the Carlsbad laboratory.
Square-Shaped Cloud in Diamond
A natural faceted diamond displays a prominent square-shaped cloud under the table.
New Emerald Production from the Curlew Mine, Western Australia
GIA’s Bangkok laboratory studies emeralds from the Curlew mine’s recently renewed production.
Gem-Quality Anorthoclase Feldspar from Southeast Vietnam
Characterizes an anorthoclase variety of alkali feldspar found in southeast Vietnam and evaluates its potential for commercial use.
Gemological and Trace Element Characteristics of Cassiterite from Yunling, China
Examines gem-quality cassiterite from southwest China and analyzes trace element chemistry to distinguish it from Bolivian cassiterite.
Laboratory-Grown Diamonds: An Update on Identification and Products Evaluated at GIA
Reviews the advancements and major trends in laboratory-grown diamonds observed by GIA since 2007.
Dance of Light and Color: Painted Labradorite
Artist Valentina Fetisova transforms labradorite cabochons into remarkable works of art.
Dance of Light and Color: Painted Labradorite
Artist Valentina Fetisova transforms labradorite cabochons into remarkable works of art.
Micro-Features of Tourmaline
Provides a visual guide to the internal features of tourmaline as well as tourmaline inclusions in other gem hosts.
Quartz with Sphalerite
A quartz crystal from the Taolin mine in China hosts a phantom of brownish orange sphalerite inclusions.
“Conch Shell” in Diamond
A transparent feather observed in a natural diamond resembles a conch shell.
Remarkably Large Akoya Bead Cultured Pearls
Strands of unusually large round Japanese akoya pearls were spotted in early 2024 in Tucson.
In Memoriam: GIA Governor Dr. Rodney Ewing
Dr. Rodney Ewing, a member of the GIA Board of Governors from 2006 to 2015, passed away earlier this month at age 77.
悼念前 GIA 理事 Rodney Ewing 博士
Dr. Rodney Ewing, a member of the GIA Board of Governors from 2006 to 2015, passed away earlier this month at age 77.
GIA Alumni Celebrate 50ᵗʰ Reunion of First New York Graduating Class
Members of the first class to complete the GIA Graduate Gemologist® program in New York City gathered.
GIA Pilots Jewelry Report Service
The Nature of the Be-Nb-Ta Containing Cloud in Natural Madagascar Blue Sapphire – An FIB/HRTEM Study
Investigates the nature of nano-inclusions of elements such as niobium, tantalum, and tungsten in the milky regions of natural beryllium-bearing sapphires.