Ruby & Spinel from Tajikistan • Moon Over the Pamirs
A 2006 mission to remote ruby and spinel localities in Tajikistan.
Beryllium-Treated Blue Sapphire • Lattice Diffusion of Corundum
The use of high-temperature lattice-diffusion heat treatment with beryllium to lighten the color of blue sapphires.
Genetics and Color Vision • Seeing Red
Do men and women have the same ability to see red? The answer might shock you.
Madagascar Ruby & Sapphire • Sorcerers & Sapphires
In search of ruby and sapphire on the lost Isle of Madagascar.
Fingerprints & Crystal Symmetry • Inside Out
A discussion of how inclusion patterns mimic crystallographic symmetry in ruby and sapphire.
Identifying Yellow Sapphire • Blue Filter in Gemology
Introducing the blue filter as a gemological tool to separate natural and Verneuil synthetic yellow sapphires.
Verneuil Synthetic Corundum • Dangerous Curves
Virtually all gemologists are aware of the curved growth lines and gas bubbles in Verneuil (flame-fusion) synthetic corundum, but few understand exactly why they occur and how they are distributed in these stones. This article clarifies these important identifying features.