Freshwater Akoyas - A Trending Misnomer for Certain Freshwater Pearls

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Fall 2025 G&G Available Now

An overview of the Fall 2025 Gems & Gemology content.

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Blue Color in Quartz Caused by Elbaite Inclusions

Blue needle-like inclusions are analyzed in three quartz spheres.

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Raw Brilliance: Nature’s Diamond Sculptures

Showcases the diverse natural shapes of rough diamonds and explores how geological processes create their unique forms.

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Gersdorffite in Quartz

Gersdorffite inclusions in quartz exhibit either triangular or hexagonal shapes when viewed from different directions.

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Cristobalite Stars and Snowflakes in Devitrified Glass

A unique inclusion scene caused by devitrification is observed in artificial glass.

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Type IIa/IaB Diamond Showing Transient Type IIb Responses

A 2.50 ct natural type IIa/IaB diamond submitted to the Dubai laboratory shifts to type IIb after deep-UV excitation.

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Extraordinary Large Bicolor Natural Rough Diamond

A 37.41 ct natural rough diamond with distinct pink and colorless zones is examined at GIA’s Botswana laboratory.

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Low-Heft Hollow Natural Pearl with an Opening

Organic-rich material is observed through an opening in a hollow natural pearl.

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Pink Diamond with Mottled Appearance

Examination of a Fancy Deep brownish orangy pink diamond reveals evidence of treatment to enhance its color.

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Trapiche Pattern Formation of Grossular Garnets

GIA’s Tokyo laboratory examines three grossular garnets displaying six-rayed black inclusions arranged in a snowflake-like pattern.

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Large Peridot from Myanmar with an Eight-Rayed Star

An eight-rayed star peridot with a star system made up of two different sets of inclusions is described for the first time.

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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.

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Unusual Yellow Diamond with a Complex Growth History

A combination of growth and dissolution features contribute to a yellow diamond’s unique shape.

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Diamond Ring Prize from an Arcade-Style Claw Game

A diamond ring from a claw game in Japan is analyzed.

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Gaseous Carbon Dioxide Phases in Paraíba Tourmaline

Immiscible two-phase fluid inclusions are investigated in a 0.48 ct Paraíba tourmaline.

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Palaeoclavaria burmitis Inclusions in Burmese Amber

Fungal inclusions are studied in two specimens of Burmese amber.

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A Guide to Diamonds with the 480 nm Absorption Band

Summarizes the features of 480 nm band diamonds, including chameleon diamonds and those with unmodified orange hues, for rapid identification or advanced gemological testing.

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External Morphology and Internal Zonal Structure of Macle Diamond

Investigates the morphological changes of macle diamonds during the growth process by exploring their three-dimensional internal zonal structure.

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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.

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