Articles Section is a showcase for 40 years of experience in the industry. It is an ever growing collection of articles and information on gemology, gems and the trade in general written by GIA gemologists on our staff. Use our long experience in the trade to increase your knowledge.
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Tanzanite Color - How it Affects Value - Judging Tanzanite Color can be difficult especially online. Learn what to look for. 06 June 2019
How to Care for your Tanzanite - An overview of Tanzanite's physical properties and how to care for it. 02 June 2019
Tourmaline Buying Guide - Learn how to judge quality in Tourmaline with this comprehensive Tourmaline Buying Guide. 15 May 2018
Reminiscences of a Childhood Mining in Kenya's Wilderness - I have been encouraged to write down some random memories of what is was like to spend so much of my early years chasing gemstones far from civilization in the African bush. 04 April 2018
Tanzanite Crystallography - An exploration into Tanzanite's crystal system with photography and videos of specimens. 11 March 2018
Yellow Sapphire from Garbatula Kenya - Rare and entirely natural. Yellow "Canary " Sapphires from Kenya are highly revered. 01 February 2018
Tanzanite Clarity Grading - How it Affects Value - Tanzanite Clarity Grades explored and explained. 10 January 2018
Inclusions in Tsavorite - An Exploration of the Inner World of Tsavorite Gemstones - An in depth article which delves into the inner world of Tsavorite gemstones. examining the different types of inclusions typically seen in this gem type and also some not so typical. Professional photography with GIA microscope and microscope camera. 01 November 2016
The Mohs Scale of Hardness - The Moh's Scale of Hardness depicting how various minerals are compared to each other for their susceptibility to scratching. 02 August 2016
Birthstones - The Definitive Guide - The definitive guide to birthstones. 29 July 2016
The Definitive Birthstone Chart - The definitive chart for Birthstones 28 July 2016
Tanzanite Cut - Often Overlooked But Very Important - The role of Tanzanite cut in how it relates to Tanzanite grades and value is often overlooked in favor of price. This is a mistake and this article explores why. 17 November 2012
Tanzanite Color Grading – So Many Systems, Which to Trust? - A guide to the different Tanzanite Color Grading systems in use in the market today. 28 October 2012
Tsavorite Mining - The Potential for Modernization - The potential for modernising small scale Tsavorite mining in Kenya and by extension making this beautiful gemstone more available to the world. 06 February 2012
Tanzanite Colors - The Amazing Variety - Tanzanites are rare and beautiful and come in a variety of colors. they also change their appearance markedly in different lights. This article explores these remarkable tenets. 15 January 2012
Gemstone Treatments - Coating and Chemical Treatments - Gemstones are treated in a myriad of different ways, some sophisticated, some not so. This article explores 2 commonly used types in the industry. 15 December 2011
Gemstone Treatments - Heating & Irradiation - Many forms of gemstone treatment exist. This article takes a look at 2 of the oldest and most common; heating and irradiation. 04 November 2011
Gemstones and Light - As most people who own gemstones have discovered, gems can look very different in different lights and even times of day. This article explores how color, light and gemstones interact and explains this phenomenon. 15 September 2011
Gemstone Cutting - The Magical Process - A cursory look at the ages old art of gemstone cutting and what makes a good cut. 20 August 2011
Color Change Garnet From Kenya - A new discovery in the renowned Taita district of Kenya has taken the gem world by storm. We take a look at the new stone and the discovery. 15 June 2010