Blue color zoning observed in some of the unusual rubies; immersed in

Strong blue color zones were observed in many of the Jegdalek rubies.

Color Change Garnet Emerald Cut 1.46 Carat - Rare Gemstone Company

Minerals, Free Full-Text

Ruby and sapphires ::: Gemology

Lab-Created Alexandrite Color Change Russian Lab-Grown Loose Gemstones Pear Shape Faceted Jewelry Ring & Pendant Size Stone

Aquamarine Emerald Cut Long 8.73 Carat - Rare Gemstone Company

Sudarat SAESEAW, Senior Manager Coloredstone Identification, MAster degree of Analytical Chemistry, G.G., FGA, Gemological Institute of America, Carlsbad, Colored stones Identification

Ren LU Research profile

Colorless zoning; immersed in methylene iodide. Photo by S. Saeseaw ©GIA.

Understanding Common Corundum Treatments