Dyed Natural Corundum as a Ruby Imitation
The gemological properties of a new ruby imitation, produced by dyeing natural colorless to pale-colored corundum, are described.
An Examination of Nontransparent “CZ” from Russia
White, pink, and black nontransparent synthetic "cubic zirconia" is currently being manufactured in Russia and marketed primarily in cabochon and bead form.
Characterization of Colorless Coated Cubic Zirconia (Diamantine)
Over the past several years, diamond simulants have entered the market that consisted of colorless cubic zirconia reportedly coated with a thin layer (e.g., represented to be 30–50 nm) of nanocrystalline diamond particles embedded in a matrix.
Lepidolite with Simulated Matrix
The authors examine an unusual crystal in matrix.
The Early History of Gemstone Treatments
The author has uncovered many ancient references to the simulation or enhancement of gemstones.
Cobalt Glass as a Lapis Lazuli Imitation
The properties of a novel gemological imitation, cobalt glass.
The Identification of Turquoise by Infrared Spectroscopy and X-Ray Powder Diffraction
Two techniques for identifying natural, treated, and synthetic turquoise are examined.
The Jade Enigma
An examination of the various simulants of of nephrite and jadeite, and how to separate them from jade.
A Simple Approach to Detecting Diamond Simulants
Contrasting the physical properties of diamond with colorless specimens to identify the most problematic diamond simulants.
Cubic Zirconia: An Update
An examination of the skull-melting technique used to produce cubic zirconia, first introduced in 1976, as well as the market status of this diamond simulant and information about its production and quality.