Documents a series of visits to Myanmar in search of exceptionally bright pinkish red spinels possessing no dark tones.

Get details on the latest research from the GIA research team, including: natural diamond geology and mining locations, causes of colors and optical features, laboratory-grown diamond research, ...

View the holiday schedule for all GIA locations worldwide.

The lapis-lazuli deposits at Sar-e-Sang in Badakhshan, Afghanistan, have provided the raw material for objects fashioned of this stone since the earliest civilizations. The mine, which lies in the ...

This article examines the history of the Ouro Preto district as well as the geology of the area and occurrence of the topaz.

Synthetic moissanite is much closer to diamond in overall appearance and heft than any previous diamond imitation; this article reports on how to identify and characterize it.

This article presents information about the CVD process, the history of its development, and properties that differentiate the resulting synthetic crystals from natural diamond.

Feature Gems & Gemology, Fall 2014, Vol. 50, No. 3 Observations on Pearls Reportedly from the Pinnidae Family (Pen Pearls) Nicholas Sturman, Artitaya Homkrajae, Areeya Manustrong, and Nanthaporn Somsa ...

Pink CVD lab-grown products can be separated from natural and treated-color natural pink diamonds by a combination of gemological and spectroscopic properties, which are explored in this study.

The history of Baja California has been closely tied to the exploitation of pearls since the 16th century.

Knowledge of the durability of a gemstone is critical to understanding the risks involved in the various setting, repair, and cleaning procedures commonly used by the jeweler. Some gemstones need ...

A large number of natural-color yellow diamonds are analyzed using grading and appearance aspects among other characteristics to clarify the differences between them and the light yellow diamonds ...