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.
A Synthetic Diamond Overgrowth on a Natural Diamond
Analysis of a diamond graded Fancy blue revealed a CVD synthetic overgrowth on natural diamond.
Large Colorless HPHT-Grown Synthetic Gem Diamonds from New Diamond Technology, Russia
Examines a new source of colorless and near-colorless gem-quality HPHT synthetic diamonds using spectroscopic and gemological analysis.
Characteristics of Gem-Quality By-Product Synthetic Zincite
Investigates the properties of synthetic zincite produced by industrial kilns in Poland.
Update on Rock Creek Sapphire Deposit
An overview of recently expanded sapphire production at the Gem Mountain mine near Philipsburg, Montana.
Blue HPHT Synthetic Diamond Over 10 Carats
Results from GIA’s recent testing of a 10.08 ct blue HPHT synthetic diamond, the largest HPHT synthetic recorded to date.
An Introduction to Synthetic Gem Materials
A synthetic gem material is one that is made in a laboratory, but which shares virtually all chemical, optical, and physical characteristics of its natural mineral counterpart, though in some cases, namely synthetic turquoise and synthetic opal, additional compounds can be present.
Synthetic Emeralds Grown by Richard Nacken in the Mid-1920s: Properties, Growth Technique, and Historical Account
Describes the chemical, morphological, and microscopic properties of the first gem-quality synthetic emeralds ever produced, offering a historical perspective on their development.
Observations on CVD-Grown Synthetic Diamonds: A Review
Explores statistical data and defining characteristics of gem-quality CVD synthetic diamonds examined by GIA since 2003.