Impregnated and Dyed Turquoise

Natural turquoise has been subjected to dyeing and three types of impregnation.

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A Jadeite Bangle Simulant: Hydrogrossular Garnet

Bangles submitted for identification are found to be not jadeite jade, but hydrogrossular garnet, an unusual choice for this form.

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Large Star Emerald

An emerald reportedly from Madagascar is cut to show asterism, a rare phenomenon in this material.

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Rare “Star and Cross” Quartz from Brazil

Two quartz specimens showing asterism and cross-shaped inclusions are analyzed.

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Serpentine Cabochon with Unusual Olive Green Color

A green cabochon from China resembling jadeite is found to be antigorite, a member of the serpentine group.

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Thai-Myanmar Petrified Woods

The properties of petrified woods originating from various localities in Thailand and Myanmar are examined.

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Coated Rock Crystal Imitation of Ruby

A coated rough rock crystal resembles a purplish red ruby.

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Color-Change Synthetic Cubic Zirconia as Peridot Imitation

A greenish yellow material set in a ring as a peridot imitation is identified as synthetic cubic zirconia.

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Coral Inclusions in Plastic

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Natural Faceted Red Rutile

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