Temples and Treasures of Southern Asia: A GIA Museum Exhibit
A photo tour of the GIA Museum’s latest exhibit featuring extraordinary crystals and gems central to the cultures of southern Asia.
Intriguing Sapphire from Montana, a New Source of Emerald in Central China, and Arkansas Turquoise
An overview of the Winter 2025 Gems & Gemology content.
The Diversity of Gemstone Deposits
Investigates deposits known for producing multiple gemstone species and the conditions that create their distinct geological settings.
An Evaluation of Turquoise from the Mona Lisa Mine in Arkansas
Examines samples of Mona Lisa turquoise to identify their chemistry and structure, revealing copper as a major elemental component of the material.
Converge 2025 Speaker Presentations
A summary of presentations from 24 industry-leading experts at Converge.
Quarterly Crystal: 𝛽-Quartz Morphology in Beryl
An aquamarine crystal from Pakistan contains a pseudomorphic quartz inclusion.
Freshwater Akoyas - A Trending Misnomer for Certain Freshwater Pearls
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GIA to Update Gemological Reports for Colored Stones
GIA will launch redesigned colored stones reports and new services on January 1, 2026.
Quarterly Crystal: Almandine-Pyrope Garnet in Diamond
A diamond octahedron from South Africa hosts a rare yellow-orange almandine-pyrope garnet crystal.
Low-Heft Hollow Natural Pearl with an Opening
Organic-rich material is observed through an opening in a hollow natural pearl.
Low-Temperature Heat Treatment of Corundum and the Behavior of the 3161 cm–1 Infrared Band
A study analyzing the thermal behavior of the 3161 cm–1 IR feature in 10 natural corundum samples from various deposits.
Suspended Pargasite Crystal in Pink Spinel
A euhedral prismatic pargasite crystal is identified in pink spinel.
Two Assembled Pearls
Natural pearl cores are used to simulate the appearance of natural pearl growth in two assembled pearls mounted in a pair of earrings.
Diamond Ring Prize from an Arcade-Style Claw Game
A diamond ring from a claw game in Japan is analyzed.
Sea Urchin–Like 3D Radial Fissures in a Heated Mong Hsu Ruby
Examination of a 1.34 ct ruby reveals a unique inclusion formed during heat treatment.
Quench-Crackled and Dyed Laboratory-Grown Sapphire
The Carlsbad lab receives a laboratory-grown colorless sapphire with weblike fractures containing concentrations of dye.
Unusual Yellow Diamond with a Complex Growth History
A combination of growth and dissolution features contribute to a yellow diamond’s unique shape.
Gersdorffite in Quartz
Gersdorffite inclusions in quartz exhibit either triangular or hexagonal shapes when viewed from different directions.
Prismatic Bicolor Dumortierite Crystal
A 63.17 ct dumortierite rough crystal is examined in the Bangkok laboratory.