Blue Sapphires from Mogok, Myanmar: A Gemological Review
A gemological analysis of blue Burmese sapphires from Mogok, based on a series of field expeditions over the last decade.
Colored Stones from the Deep
The first installment of this column discusses the formation of colored stones from the crust-mantle transition and below.
Burmese Blue Sapphire and Peridot from Mogok and a History of Emerald Mining in Habachtal, Austria
An overview of the Winter 2021 Gems & Gemology content.
Banded Turquoise from Zhushan County, Hubei Province, China
Researchers examine six specimens of banded turquoise, obtained through long-term cooperation of local miners in Zhushan County.
Blue Zircon Reportedly from Malawi
A reported new source of blue zircon in Malawi yields rough material for beautiful finished stones in the gem trade.
History of Emerald Mining in the Habachtal Deposit of Austria, Part I
Contributes to the mining history of Austria’s Habachtal region, which is believed to be one of the earliest emerald deposits.
Color-Zoned Cat’s-Eye Chrysoberyl
The Tokyo lab recently identified a unique localized distribution of cloud-like inclusions in a chrysoberyl.
Star Rhodochrosite
The Carlsbad lab received a rhodochrosite cabochon featuring rhomboid-shaped fluid inclusions, causing a four-rayed star.
Gemological Characterization of Peridot from Pyaung-Gaung in Mogok, Myanmar
Examines the mining and the internal, spectroscopic, and chemical features of peridot from this deposit, which possesses a rich olive green color and is available in large sizes.
Vaterite Found on a Strand of Freshwater Cultured Pearls
An unusual formation of vaterite was identified on the surface of numerous freshwater cultured pearls throughout a single strand.
GSA Meeting – GIA Session
An overview of GIA’s presentations at the annual Geological Society of America (GSA) meeting held in Portland, Oregon.
Biogenic Carbon in Pink Corundum from Southern West Greenland
Recent studies of pink corundum in Greenland suggest that the presence of graphite created the conditions that facilitated corundum formation.
New Record Size for CVD Laboratory-Grown Diamond
GIA’s New York laboratory reports a new record size for CVD laboratory-grown diamond.
GIA Grades the Most Important Diamonds in the World – Including Yours
CARLSBAD, Calif. – Dec. 2, 2021 – The joy diamonds bring to people’s lives and the confidence inspired by a diamond grading report from the experts at GIA are at the center of GIA’s first new global consumer marketing campaign in more than a decade.
GIA權威評級, 為摯愛守護一生
CARLSBAD, Calif. – Dec. 2, 2021 – The joy diamonds bring to people’s lives and the confidence inspired by a diamond grading report from the experts at GIA are at the center of GIA’s first new global consumer marketing campaign in more than a decade.
Book Review: The Secret Teachings of Gemcutting: 50 Classic Gemstone Designs
Review of The Secret Teachings of Gemcutting: 50 Classic Gemstone Designs, by Justin K. Prim.
GIA Board Meets to Set Priorities; Welcomes New Governors
CARLSBAD, Calif. – Nov. 17, 2021 – The GIA Board of Governors held their first in-person meeting in two years, Nov. 5 – 8, in Carlsbad, California.
HPHT-Processed Diamond with Counterfeit GIA Inscription
Careful comparison of two GIA reports reveals a fraudulent inscription on a laboratory-produced diamond presented as a natural.