Gem Paintings from Thailand
Paintings created from uncut gem fragments are seen at Tucson’s GJX show.
Importance of the Secondary Market for Fine Gems
Exceptional gems that are recirculated in the gem market make an impact at the Tucson shows.
Brazil’s Enigmatic Diamonds, Cuprian Liddicoatite, and Silicon in Corundum
An overview of the Spring 2017 Gems & Gemology content.
Magnificent Sapphires from Montana’s Rock Creek Mine
A look at the 2016 sapphire production from Montana’s Rock Creek deposit.
Exceptional Freeform Tanzanite and Oregon Sunstone Rings
A family sources, designs, and carves gems for extraordinary jewelry and pieces.
Negative Crystals in Sapphires
Sapphires from Baw Mar host multiphase inclusions in appealing patterns.
Cuprian Liddicoatite Tourmaline
Identifies 13 copper-bearing tourmalines, which have traditionally been assumed to be elbaite species, as liddicoatite.
Unusual Dark Orangy Red Cordierite
A cordierite with a color not seen in the GIA lab is examined in New York.
Three Faceted Collector Specimens
Three mineral species, not previously seen in the Carlsbad lab, are examined.
The Role of Silicon in the Color of Gem Corundum
Considers the previously unreported but critical impact of silicon on the coloration of gem-quality sapphire.
Pyrope-Spessartine Color-Change Garnet with a High Grossular Component
A color change in rough garnet is observed and plotted in GIA’s Carlsbad lab.
Japanese Jadeite: History, Characteristics, and Comparison with Other Sources
Examines the sources, color, texture, and chemical composition of jadeite from Japanese deposits.
GIA发现覆合钻石
Analysis of a diamond graded Fancy blue revealed a CVD synthetic overgrowth on natural diamond.
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