Field Report Gems & Gemology, Fall 2016, Vol. 52, No. 3 Bead-Cultured and Non-Bead-Cultured Pearls from Lombok, Indonesia Nicholas Sturman, Jeffery Bergman, Julie Poli, Artitaya Homkrajae, Areeya ...

A chemical and spectroscopic comparison of two purple gem spinel samples, one of them the first reported example of a spinel with a saturated purple color caused predominantly by chromium and cobalt.

GIA ensures accurate gemological measurements across its global laboratories through rigorous metrology practices, including systematic instrument calibration, validation from traceable standards, and ...

Shows how the color of Madagascar sapphire is lightened with heating to relatively low temperatures below 1350°C.

The GIA laboratory in Ramat Gan, Israel, will end operations by the end of 2024 due to changes in the global diamond industry that resulted in significant declines in submissions from local clients ...

Diamonds have a long history as a premier gemstone—a natural consequence of their beauty, rarity, and superlative physical properties such as extreme hardness. Diamonds that are mined for use as ...

Provides a visual guide to the internal features of tourmaline as well as tourmaline inclusions in other gem hosts.

GIA’s Bangkok laboratory encounters two phenomenal gems while examining a parcel of emeralds from Pakistan.

The micro-world of gems lies at the very core of gemology. Information gathered from observations through the microscope serves as the very foundation for many conclusions drawn on a specimen, ...

The quality and size of this 4.04 ct CVD-grown diamond ring demonstrate the advancing technology in laboratory-grown diamonds.

A study on American ruby and sapphire from Rock Creek, Montana, unveils a few geochemical mysteries.

A unique cabochon specimen composed of “bloodshot” iolite and sunstone offers a visually pleasing combination.