Corundum Colors

Jewelry Discussion
1

This is in reply to Gerry’s post in the rare white turquoise thread.

The book HANDBOOK OF GEM IDENTIFICATION by Richard T. Liddicoat,
jr., 11th Edition page 237 under the category of Corundum, lst
paragraph, 4th line, I quote the following:

“Ruby includes only the medium to dark tones of red to
violetish-red. All other colors including purple, violet, and light
red are properly called sapphire.”

Diane Sadel
http://www.sweetgemstones.com

2

I’ve always used, as a diagnostic tool, the fact that a ruby is
ideochromatic and takes it’s color from chromium. If I can detect
absorption lines in its spectrum then it’s a ruby if not then it’s a
red, pink etc. corundum. Likewise some green beryls do not show
chromium absorption lines and they are correctly designated as green
beryl.

Tony Konrath
Gold and Stone
http://www.goldandstone.com