Article Search Results

Show Filters
Showing 14 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

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

Article
Spring 2015 G&G Examines Blue Spinel, Chinese Jewellery Design and the Latest in Synthetics

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

Read More

Natural Mixed Cape Diamond
Mixed-Type Cape Diamond

A Fancy orangey-yellow “cape” diamond featured an unexpected 480 nm band, a defect normally associated with orange colour.

Read More

Diamond with High Concentration of Nickel

Analysis of Fancy Light greenish yellow diamond leads to detection of nickel, as well as an inclusion that gives a colour-change effect.

Read More

Fluorescence produced by optical defects in diamond: measurement, characterisation and challenges

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

Read More

Optical defects in diamond: a quick reference chart

A simple chart of optical defects in diamond, including those that produce colouration and fluorescence colours.

Read More

Coloured Diamonds in the Aurora Butterfly of Peace Collection
The “Type” Classification System of Diamonds and Its Importance in Gemmology

Knowledge of type allows gemmologists to better evaluate if a diamond might be treated or synthetic, and whether it should be sent to a laboratory for testing.

Read More

Treated-Colour Pink-To-Red Diamonds from Lucent Diamonds Inc.

Using a multi-step process, Lucent Diamonds has developed a new treatment process for certain natural diamonds that creates colours from pink-purple to red to orangey brown.

Read More

Lab-Grown Coloured Diamonds from Chatham Created Gems

This article compares some of Chatham Created Gems’ synthetic coloured diamonds to natural diamonds and explains the results.

Read More