Feature
Gems & Gemology, Fall 1996, Vol. 32, No. 3
Russian Flux-Grown Synthetic Alexandrite
Karl Schmetzer, Adolf Peretti, and Olaf Medenbach, and Heinz-Jürgen Bernhardt
Synthetic alexandrite is being flux-grown in Russia in a molybdenum-, bismuth-, and germanium-bearing solvent by means of the reverse-temperature gradient method. Characteristic properties include habit, twinning, growth patterns, residual flux inclusions, trace-element contents, chemical zoning, color zoning, and spectroscopic features in the visible and infrared ranges. The relationship between production technique and characteristic properties is discussed, and diagnostic properties that can be used to distinguish these synthetics from natural alexandrite are disclosed.