Article Search Results

Show Filters
Showing 87 results for "*"
Fancy Dark brown to Fancy black Marange diamonds
Black Diamonds from Marange (Zimbabwe): A Result of Natural Irradiation and Graphite Inclusions

Characterizes a suite of 40 natural brown to black diamonds from this deposit so that they can be distinguished from suspected treated black diamonds.

Read More

Optimizing Face-Up Appearance in Colored Gemstone Faceting

How contrast patterns can increase perceived brightness and optimize a gemstone's appearance.

Read More

Fluorescence Produced by Optical Defects in Diamond: Measurement, Characterization, and Challenges

How variations in UV lamp output can affect observed fluorescence color and intensity.

Read More

Rainbow hematite from Brazil’s Andrade mine.
Iridescence in Metamorphic “Rainbow” Hematite

Analyzes the substructures that cause the intense iridescence observed in “rainbow” hematite from Minas Gerais, Brazil.

Read More

A heart-shaped piece of pink drusy hangs from a gold chain.
Article
Dreamy Drusy: Minute Crystals Shimmer in Dramatic Designs

Drusy jewelry has surged in popularity in recent years. Celebrities wear it on the red carpet and designers clamor for it at gem shows.

Read More

The Identification of Blue Diffusion-Treated Sapphires

Blue diffusion-treated sapphires are becoming more prevalent than ever before.

Read More

Article
Pyrope Garnet and Montana Sapphires Highlight Winter 2015 G&G

G&G Brief presents an overview of the content of the Winter 2015 issue of Gems & Gemology.

Read More

Color zoning in amethyst from Boudi, Morocco
Amethyst from Boudi, Morocco

An introduction to Moroccan amethyst, which features distinctive color zoning and inclusions.

Read More

Colombian Emeralds
Classifying Emerald Clarity Enhancement at the GIA Gem Trade Laboratory

One of the greatest concerns with emerald filling is the degree of clarity enhancement such treatment represents

Read More

Optical Defects in Diamond: A Quick Reference Chart

A simple chart on optical defects in diamond, including those that produce coloration and fluorescence colors.

Read More