A new type of invisible marking in CVD diamonds suggests a possible security measure.

A brownish yellow cabochon submitted as cat’s-eye chrysoberyl is identified as artificial glass.

A rare example of faceted gem-quality zektzerite is examined in GIA’s Carlsbad laboratory.

Two items submitted as emerald to the New York lab are identified as plastic manufactured products.

The Carlsbad laboratory receives a very rare and fragile 3.09 ct brucite.

An overview of the Summer 2024 Gems & Gemology content.

GIA’s Mumbai laboratory reports on the study of Pteria sterna shells with visible protuberances.

Examination of an akoya keshi pearl in the Mumbai laboratory reveals rare seed features and an acicular structure.

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

A rainbow-colored wavy pattern is revealed under the surface of a non-bead cultured freshwater pearl.

Particle clouds close to the surface of a blue sapphire create a scene reminiscent of tire tracks in snow.

A pen shell examined in GIA’s Mumbai laboratory exhibits a pattern resembling the skin of a snake.

A pink sapphire from Mogok hosts a large surface-reaching spinel inclusion.

A Star of David pattern is observed within partially healed fissures in a sapphire from southern Vietnam.

The Tokyo laboratory reports on a submitted stone composed of both chrysoberyl and alexandrite.

A nacreous-looking calcite pearl exhibiting red X-ray fluorescence is documented for the first time at GIA.

Testing of five CVD laboratory-grown diamonds submitted to the New York laboratory reveals post-growth treatment to achieve fancy colors.