Gota de Aceite–Like Effect in a Brazilian Emerald
GIA’s Tokyo laboratory examines a Brazilian emerald with a gota de aceite–like effect characteristic of Colombian emeralds.
Rare Kashmir Star Sapphire
A stunning large Kashmir star sapphire, set in a combination ring and pendant, is submitted to the New York laboratory.
A Synthetic Moissanite Presented as Natural Diamond Rough
The New York laboratory identifies a sample submitted for a colored diamond identification and origin report as synthetic moissanite.
Update on Inclusions in Emeralds from Davdar, China
Testing reveals interesting inclusions in Chinese emeralds to be calcite and dolomite.
“Floating Flower” Inclusions in Aventurine Quartz Bangle
Lab analysis proves that a bangle with “floating flower” inclusions believed to be jadeite jade or albite is actually highly translucent aventurine quartz.
Historic Sales of Pink and Blue Diamonds from the Argyle Mine
Rio Tinto sells its final collections of pink and blue Argyle diamonds at record-breaking prices.
Update on Mining Activity at Yogo Gulch, Montana
Renewed mining interest in Montana promises a return of the famous Yogo sapphire to the gem trade in the coming years.
Unique Circuit Board–Like Surface Pattern on Tourmaline
Microscopic observation by the Tokyo lab revealed a mysterious networked pattern, resembling that of a circuit board, covering the overall surface of a blue-green tourmaline.
Exceptionally Large and Well-Saturated Orange Sapphire
A notable 31.06 ct well-saturated orange sapphire was recently submitted to the Carlsbad laboratory.
Natural Black Coral with Polyp Structure
Examination of a large black oval cabochon reveals an intense orangy brown and black polyp structure, indicating natural black coral.
Windmill Zoning in Tourmaline
Pink faceted tourmaline reveals unique colorless windmill-shaped zoning.
Quartzite Bangle with Fuchsite Inclusions
A quartzite bangle mimics the appearance of jadeite jade.
Barite-Calcite Composite as Imitation “Wulanhua” Turquoise from Hubei Province, China
“Wulanhua” turquoise bracelet identified as composite material made of barite, calcite, and blue dye.
Characteristics of Amber with Irradiation Treatment
A study of the effects of irradiation treatment on amber.
The Discovery of Davemaoite, the CaSiO3 Perovskite, in a Diamond from Earth’s Lower Mantle
Davemaoite identified in a diamond from Orapa, Botswana.
Gray “Spinel Sisters”
Two rare gray spinel stones stand out at the AGTA show for their exceptional size, quality, and color.
Inclusions and Spectroscopic Features of Yellowish Green Enstatite
Close study of six bright yellowish green enstatite samples reveals cause of color and four-rayed asterism.
Many Faces of Wavellite
An Arkansas lapidarist shares his work with wavellite and explains his stabilization process.
Old Techniques Reimagined: Maki-e Pearls
An ancient Japanese lacquer technique applied to cultured pearls creates unique pieces of art.
Hydrothermal Synthetic Ruby
A transparent cushion-cut hydrothermal synthetic ruby was recently submitted to Carlsbad laboratory for an identification report.
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