Colombian Emerald Industry: The New Generation
Luis Gabriel Angarita and Edwin Molina share their experiences and perspective on the Colombian emerald industry.
Turquoise from Western Arkansas
A report on turquoise from the only known U.S. deposit outside of the Southwest.
Irradiated and Annealed Blue Type Ia Diamond
Examination shows that a diamond was subjected to a multi-step process in order to introduce a blue color.
Fancy Deep Brown-Orange CVD Synthetic Diamond
A CVD-grown diamond shows an unexpected treatment-caused color.
Fracture-Filled Diamond with "Rainbow" Flash Effect
The material used to fill a large fracture in a diamond yields an unexpected iridescence under two different illuminations.
Unheated and Unusual Colors
Margit Thorndal of Madagascar Imports offers her perspective on the colored stone market.
Inclusions in Natural, Synthetic, and Treated Ruby
Provides a visual guide to the internal features of natural, synthetic, and treated rubies.
Filled Pearl with Surface Features
A pearl, thought to be natural, is revealed to be a bead-cultured specimen with a pre-drilled nucleus.
Update on Dyed Hydrophane Opal
Opal purportedly from a new deposit is found to be dyed.
Coated Beryl Imitating Emerald
Coating on a beryl demonstrates the importance of thorough examination of jewelry and gem materials.