One of the greatest gemological challenges is determining if a ruby or sapphire has been heat treated. UV fluorescence can assist in that identification, as well as detecting fillers in emerald.
Fiber-optic lighting is one of the most useful form of lighting in the gemological laboratory. With it, we are able to see inclusions that would otherwise be invisible.
Gübelin, Eduard J. & Koivula, John I. (2005) Photoatlas of Inclusions in Gemstones, Volume 2. Opinio Publishers, Basel, Switzerland, 830 pp. ISBN 978-3855040957
The examination of a yellow sapphire provides a lesson in the power of gemological microscopy.
A discussion of rutile silk in corundum (ruby & sapphire) and its use in detecting artificial heat treatment. Careful examination of these "silk" inclusions can provide vital clues to unmask heated gems.
Read moreA discussion of the flux-healing treatment of rubies. This article was awarded the Richard T. Liddicoat Journalism Award by the American Gem Society in 2005.
An examination of the problem of separating pink sapphire and padparadscha from ruby.