Paraíba Tourmaline Melee: An Entry-Level Market Perspective

A look at Paraíba tourmaline melee, which offers a more accessible price point for consumers.

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Gem-Quality Spinel from Southern Malawi

Parcels of rough spinel recently mined in Malawi were offered at the AGTA show.

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Evil Eye in a Flux-Healed Mong Hsu Ruby

The mirror reflection of a flux-healed fissure from a step pavilion facet in a Mong Hsu ruby creates an interesting inclusion scene.

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Update on Montana’s Rock Creek Sapphire

Potentate Mining expands its mining operation and hosts the first Montana sapphire tender in Bangkok.

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Irreversible Photochromism in Synthetic Sapphire

The first documented case of corundum with irreversible photochromism encountered at GIA.

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Devitrified Glass “Pom-Poms” in Ruby

Devitrified glass inclusions resembling pom-poms or sea urchins are observed in a clarity-enhanced ruby.

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Rock Crystal Quartz Skull

A remarkable skull carved from quartz crystals mined in Arkansas is submitted to the Carlsbad laboratory.

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Kyanite in Quartz

Eye-visible kyanite inclusions give this 7.83 ct quartz its light blue color.

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Phenomenal Gems

A look at the most popular phenomenal gems exhibited at the 2025 Tucson gem shows.

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Natural Non-Nacreous Pearls from Various Marine Mollusks

The Bangkok laboratory studies 35 loose non-nacreous pearls from a wide range of marine mollusk species.

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New Deposit of Pezzottaite from Madagascar

A highly saturated purplish pink to red pezzottaite from a new deposit in Madagascar is encountered in Tucson and tested by GIA researchers.

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Spiral Patterns on a Non-Nacreous Pearl

A 6.79 ct orange pearl displays a fascinating spiral pattern.

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“Bubble Obsidian” from Armenia

An exhibitor at the 22nd Street show offers an unusual type of obsidian from Armenia.

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Enormous South Sea Cultured Pearl with Filled and Partially Hollow Structure

Examination of a gigantic South Sea bead cultured pearl reveals an intriguing internal structure.

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Assembled Bead Cultured Half-Pearl

Investigation in the Carlsbad laboratory reveals a pearl submission is not mabe as initially believed.

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Green Jadeite-Omphacite from Guatemala

Bright green and nearly transparent jade from Guatemala, similar to jade from Myanmar, was available in Tucson.

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Black Opal with Unique Play-of-Color

A black opal cabochon set in a ring displays vivid orange play-of-color.

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Dendritic Patterns in Emerald

A partially filled fissure in an emerald exhibits patterns resembling natural foliage.

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Fancy Vivid Yellow HPHT-Grown Diamonds

A report on a submission of 26 yellow HPHT-grown diamonds from the Hong Kong laboratory.

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Rose-Shaped Cloud Inclusion in Diamond

A cluster of cloud inclusions in diamond forms a petal-like structure resembling a rose.

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