X-ray Computed Microtomography Applied to Pearls: Methodology, Advantages, and Limitations
X-ray computed microtomography reveals the internal features of pearls with great detail.
Gemological Characteristics of Saltwater Cultured Pearls Produced After Xenotransplantation
Spectroscopic and radiographic study of experimental saltwater cultured pearls produced from xenotransplantation between P. margaritifera and P. maxima.
X-ray Computed Microtomography: Distinguishing Natural Pearls from Beaded and Non-Beaded Cultured Pearls
The distinction of natural from cultured pearls traditionally has been based on X-radiography.
“Fishbone” Inclusion in a Burmese Peridot from Mogok
Examination of Burmese peridot with impressive size, color, and clarity reveals a fishbone-shaped inclusion.
Spray of Columbite Crystals in Topaz
A cluster of bladed columbite crystals is identified in colorless topaz.
Turquoise Planet Earth
A sphere of Armenian turquoise with natural brown matrix material mimics planet Earth.
Faceting Transparent Rhodonite from Broken Hill, New South Wales, Australia
Transparent rhodonite is considered one of the most difficult of all gems to facet because of its perfect cleavage and brittle, uneven fracture.
钻石中非同寻常的哑铃状内含物 (英语)
Examination of a 0.40 ct near-colorless round brilliant diamond with a large inclusion resembling a dumbbell
Sapphires from Thammannawa, Kataragama Area, Sri Lanka
The February 2012 discovery of high-quality blue sapphires at Thammannawa near Kataragama in southeastern Sri Lanka has intensified gem mining and exploration in the surrounding area and all over the country.
The Distinction of Natural from Synthetic Alexandrite by Infrared Spectroscopy
A useful way to identify stones that contain no distinguishing inclusions.
Update on Ammolite Production from Southern Alberta, Canada
There have been a number of changes in Ammolite production from southern Alberta, Canada, since 2001.
Identification of Natural, Reconstructed, and Imitation Root Amber
Three types of root amber beads submitted for identification are analyzed in Wuhan, China.
A “Cobalt Blue” Gahnospinel
Cobalt is identified as the primary coloring agent in an intense blue specimen of gahnospinel at GIA’s Bangkok laboratory.
Large Faceted Pallasitic Peridot
A large specimen of extraterrestrial peridot is analyzed at the Carlsbad laboratory.
Aegirine in Poudretteite
Aegirine inclusions are observed in two samples of poudretteite from Mogok.
Sweet Home Mine Rhodochrosite from 1888
A rhodochrosite on display at AGTA dates back more than a century to Colorado’s Alma Mining District.
Two Pearls of Indian Cultural Significance
Two pearls representing Indian deities were recently examined in the Mumbai laboratory.
Ancient Script-Like Serpentine in Brown Peridot
Examination of a brown peridot xenocryst reveals thread-like serpentine inclusions resembling ancient text.
37th International Gemmological Conference
A report from the 37th IGC, held in late October 2023 in Tokyo.
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