The Very Deep Origin of the World’s Biggest Diamonds
Explores an exceptional family of diamonds, referred to as “CLIPPIR” (Cullinan-like, Large, Inclusion-Poor, Pure, Irregular, and Resorbed), that formed in a superdeep environment.
Inclusions in Natural, Synthetic, and Treated Ruby
Provides a visual guide to the internal features of natural, synthetic, and treated rubies.
Saltwater Pearls from the Pre- to Early Columbian Era: A Gemological and Radiocarbon Dating Study
Examines 85 saltwater natural pearls, reportedly harvested from the Caribbean islands off the coast of Venezuela during the early 16th century, to determine their age.
Synthetic Star Sapphires and Rubies Produced by Wiede’s Carbidwerk, Freyung, Germany
Details the process used by Wiede’s Carbidwerk to produce star synthetic corundum from the mid-1950s through the 1970s.
Amethyst from Boudi, Morocco
An introduction to Moroccan amethyst, which features distinctive color zoning and inclusions.
Characteristics of Gem-Quality By-Product Synthetic Zincite
Investigates the properties of synthetic zincite produced by industrial kilns in Poland.
Solution-Generated Pink Color Surrounding Growth Tubes and Cracks in Blue to Blue-Green Copper-Bearing Tourmalines from Mozambique
Several transparent, faceted, blue to blue-green copper-bearing tourmalines containing growth tubes and cracks surrounded by sleeves of pink color were examined for this report.
A New Deposit of Gem-Quality Grandidierite in Madagascar
Reviews the properties of exceptionally pure grandidierite from a new source.
Sapphires from the Sutara Placer in the Russian Far East
Studies the formation and chemical composition of the largely unexamined alluvial sapphires from Russia’s Jewish Autonomous District.
A Study of the Gems in Ciborium from Einsiedeln Abbey
The gemstones that adorn a late-16th-century ciborium from Einsiedeln Abbey in Einsiedeln, Switzerland.