Sugar/Heat-Treated Opal
At the AGTA show, lapidarist James Carpenter explains his use of sugar/heat treatment to enhance opal.
Unusual Repair of a Natural Emerald
Glass identified as the raw material used to conceal damage of a natural emerald.
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.
Amber Filled with Epoxy Resin
Gulf countries experience an increase in epoxy resin filling in amber rosary beads.