Article Search Results

Show Filters
Showing 7 results for "*"
Three pieces of labradorite with yellow, blue and green flashes of color.
Article
Optical Effects of Phenomenal Cabochons

Learn how the structure, inclusions and properties of some gemstones interact with light to create unusual visual effects.

Read More

An oval shaped 33.40 ct white Australian opal and diamond pendant/brooch set in platinum.
Article
The Enigmatic Gemstone: Opal’s Playful Dance with Light

Opal’s play-of-colour is a lyrical dance: sometimes a grand jeté of bold, broad flashes of colour or smaller, quicksteps of pinpoint flashes.

Read More

GG WN15 Cover
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

Opal with six-rayed star
Article
Star Opal

An opal featuring a rare six-rayed star is examined in GIA's Bangkok lab.

Read More

Abstract Header from the 2009 issue of Gems & Gemology
Abstracts; Summer 2009

This article, from the Summer 2009 issue of Gems & Gemmology, is a compilation of abstracts of important gemmology-related articles published outside of Gems & Gemmology.

Read More

Opal from Queretaro, Mexico: Occurrence and Inclusions

An examination of play-of-colour opal from Mexico and its variety of inclusions.

Read More

Treated Andamooka Matrix Opal
Treated Andamooka Matrix Opal

Matrix opal from Andamooka, in South Australia, is a precious opal-included porous rock that is commonly colour enhanced (carbon impregnated) to imitate the highly prized black opal from Lightning Ridge in northern New South Wales, Australia.

Read More