“Diffusion Ruby” Proves to be Synthetic Ruby Overgrowth on Natural Corundum
A relatively new production of red corundum, reportedly from Bangkok, has been offered for sale in recent years.
An Introduction to Synthetic Gem Materials
A synthetic gem material is one that is made in a laboratory, but which shares virtually all chemical, optical, and physical characteristics of its natural mineral counterpart, though in some cases, namely synthetic turquoise and synthetic opal, additional compounds can be present.
Synthetic Emeralds Grown by Richard Nacken in the Mid-1920s: Properties, Growth Technique, and Historical Account
Describes the chemical, morphological, and microscopic properties of the first gem-quality synthetic emeralds ever produced, offering a historical perspective on their development.
Confocal Micro-Raman Spectroscopy: A Powerful Tool to Identify Natural and Synthetic Emeralds
More than 300 natural and synthetic emeralds from various sources were examined with confocal Raman spectroscopy.
The Chromium Content of Lechleitner Synthetic Emerald Overgrowth
The higher the chromium content in synthetic emerald overgrowth, the darker the coating and appearance of the stone will be.
Dual-Color Double Stars in Ruby, Sapphire, and Quartz: Cause and Historical Account
Examines a form of asterism comprising two six-rayed stars, one white and one that exhibits the stone’s bodycolor. Firsthand accounts and a survey of patent documents reveal that diffusion has been used to create or enhance this optical phenomenon in synthetic and possibly natural corundum since the 1950s.
Abstracts; Fall 1991
This article, from the Fall 1991 issue of Gems & Gemology, is a compilation of abstracts of important gemology-related articles published outside of Gems & Gemology.
Abstracts; Summer 1991
From the Summer 1991 issue of Gems & Gemology, a summary of important gemology-related articles published in other journals.
Gemological Investigation of a New Type of Russian Hydrothermal Synthetic Emerald
Tairus, in Novosibirsk, has produced yet another new type of Russian hydrothermal synthetic emerald.
The Lennix Synthetic Emerald
An examination of the gemological properties of a French flux fusion-grown synthetic emerald.