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Cat's-eye demantoid with well-aligned horsetail inclusions.
Cat's-Eye Demantoid and Brown Andradite with Horsetail Inclusions

The examination of two unusual garnets results in identifications issued for the first time in GIA's colored stone report records.

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Experimental steps of DNA extraction and purification.
DNA Techniques Applied to the Identification of Pinctada Fucata Pearls from Uwajima, Ehime Prefecture, Japan

Shows how genetic material extracted from small amounts of pearl powder can be a useful indicator of this akoya cultured pearl species.

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Rough and faceted natural-color green diamonds.
Natural-Color Green Diamonds: A Beautiful Conundrum

Characterizes diamonds with exceptionally rare natural green color, based on GIA’s extensive database of samples.

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Orange pear-shaped pyrope-spessartine-grossular garnet.
Unusual Orange Pyrope-Spessartine-Grossular Garnet

A garnet proves to have a much higher grossular component than initially expected.

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Strand of small akoya bead-cultured pearls.
Very Small Akoya Cultured Pearls

A selection of very small akoya cultured specimens demonstrates the challenges gemologists face when determining pearl origin.

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Diamond and fraudulent inscription.
HPHT-Processed Diamond Fraudulently Represented as Untreated

An HPHT-treated round brilliant diamond with an inscription that presents as a GIA report number is found to be inconsistent with the institute's report, previously issued for an untreated diamond.

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Article
Atypical “Beading” in the Production of Cultured Pearls from Australian Pinctada Maxima

In 2011, the authors began to see cases of low-quality natural pearls being used as unconventional “beads” for cultured nacre growth.

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Bracelet containing akoya cultured pearls from Australia
Akoya Cultured Pearl Farming in Eastern Australia

Characterizes the akoya cultured pearls produced on the eastern shoreline of Australia using native Pinctada imbricata fucata mollusks.

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Micro-Features of Ruby
Inclusions in Natural, Synthetic, and Treated Ruby

Provides a visual guide to the internal features of natural, synthetic, and treated rubies.

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Three cultured pearls, one natural
Real-Time Microradiography of Pearls: A Comparison Between Detectors

Compares the image quality provided by real-time microradiographic imaging (RTX) units fitted with two different detectors: an image intensifier (II) and a flat panel detector (FPD).

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