
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.

Portrait of a Paraíba Rough: Challenging Gems in Hard Times
Many variables were involved in the sale and manufacture of a beautiful rough gem during difficult times.

Gems & Gemology at Ninety: Consistency and Change
An overview of the Summer 2024 Gems & Gemology content.

Blister Pearl vs. Shell Blister from Pteria sterna
GIA’s Mumbai laboratory reports on the study of Pteria sterna shells with visible protuberances.

An “Eye” on a Tridacninae Pearl
A Tridacninae pearl exhibits a flame structure resembling an eye.


“Snail” in Diamond
While different types of inclusions often occur independently within diamond, it is quite rare to find more than one occurring simultaneously, let alone in contact with each other.

Bicolor Chrysoberyl with Chrysoberyl and Alexandrite Zones
The Tokyo laboratory reports on a submitted stone composed of both chrysoberyl and alexandrite.

Calcite Pearl with Red X-Ray Fluorescence
A nacreous-looking calcite pearl exhibiting red X-ray fluorescence is documented for the first time at GIA.

Large Treated-Color CVD Laboratory-Grown Diamond Rings
Testing of five CVD laboratory-grown diamonds submitted to the New York laboratory reveals post-growth treatment to achieve fancy colors.

Large Tridacna Shell with a Blister Pearl and a Shell Blister
A large shell submitted to the Mumbai laboratory exhibits both a blister pearl and a shell blister.

Seed Features in an Akoya Keshi Pearl
Examination of an akoya keshi pearl in the Mumbai laboratory reveals rare seed features and an acicular structure.

Graphite in Sapphire
A three-phase fluid inclusion containing graphite is observed in a Sri Lakan sapphire.

Characteristics of Treated Rubies from Greenland


Special Hair-Like Inclusions in Quartz
A close look at inclusions in a variety of “rabbit hair” quartz samples.
Sustainability Conference at JCK
GIA participates in two sustainability panels during the 2023 JCK Las Vegas show.

Unique Colombian Emerald and Matrix Suite
A look at a unique matching set of emerald and brown matrix cabochons from the Muzo mine in Colombia.

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