Article Search Results

Show Filters
Showing 16 results for "*"
A face-up view of a cushion cut diamond with blue color.
Article
Gems & Gemology’s 7 Most Unusual Encounters from 2019

Check out some of the most interesting and unusual diamonds and coloured stones submitted to GIA’s laboratories in 2019.

Read More

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

Article
Diamond Cut: The Wow Factor

Learn the basics of the GIA Cut Grading System for round brilliant cut diamonds to help pick out your perfect diamond.

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

Nanocut Plasmaetched Diamonds
Cutting Diffraction Gratings to Improve Dispersion (“Fire”) in Diamonds

A new microlithography process developed to create high-resolution diffraction grating patterns on portions of certain facets can improve the dispersion of light and thus the amount of “fire” in a diamond.

Read More

Article
Summer 2015 G&G: Dual-Stars, Photomicrography Guide, Rubies from Tajikistan, New Micro-World Section

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

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

A History of Diamond Treatments

Modern gemmologists and diamantaires are faced with a broad spectrum of colour and clarity treatments ranging from the simple to the highly sophisticated.

Read More

Diamonds in Their Initial States, After UV Exposure and After Heating
Colour Alterations in CVD Synthetic Diamond with Heat and UV Exposure: Implications for Colour Grading and Identification

In response to heat and UV exposure, some synthetic diamond gemstones grown by chemical vapor deposition exhibit large, reversible changes in colour.

Read More

0.76 ct HPHT-treated Diamond
“Fluorescence Cage”: Visual Identification of HPHT-Treated Type I Diamonds

HPHT-treated type I diamonds of various colours may exhibit unusually intense fluorescence at the facet edges and junctions.

Read More