The optical phenomenon of iridescence creates a beautiful pearly rainbow effect in an abalone shell.

Analyzes a group of 23 freshwater “Edison” pearls (a trade name referring to near-round freshwater cultured pearls, usually shell bead cultured) using various gemological and advanced instrumental techniques.

Inclusions can be found in a variety of different gemstones; they create a window that allows the viewer to picture a stone’s formation history.

A rare transparent and near-colorless sodalite contains two-phase inclusions linking it to its ancient formation.

In a delightful juxtaposition, a diamond-shaped cloud inclusion appears in the center of a 0.53 ct round brilliant diamond.

Provides a visual guide to the internal features of natural, synthetic, and treated spinel, as well as inclusions of spinel in other gemstones.

Presents a method for accurately predicting the color of a gem material when viewed in any direction as long as the polarized spectra and the viewing angle relative to the c-axis are known.

Provides criteria for detecting the resin filling of turquoise, an advanced treatment that reduces porosity and can dramatically improve appearance and stability.

A graduate of GIA’s Hong Kong Jewelry Design program hopes her award-winning design will help raise environmental awareness.

An overview of how the gem and jewelry trade, from miners to manufacturers, and from designers to dealers, dealt with the many challenges posed by the pandemic.

The Carlsbad laboratory recently examined a Mexican opal containing a rare fluid inclusion with a freely moving gas bubble.

Abnormal fluorescence supports the likelihood that this amber bracelet had been “baked” to enhance its color.