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The 1990s witnessed important developments in the commercial viability of gem-quality synthetic diamonds.
Read MoreAn investigation of the difference between synthetic opal and opal simulant.
Read MoreThe gemmological properties of a new ruby imitation, produced by dyeing natural colourless to pale-coloured corundum, are described.
Read MoreWhite, pink and black nontransparent synthetic "cubic zirconia" is currently being manufactured in Russia and marketed primarily in cabochon and bead form.
Read MoreA plastic imitation opal that shows true play-of-colour was advertised as "new" and offered for sale under the trade name "Opalite" at the Gem and Lapidary Dealers Association (GLDA) Tucson show in February 1988.
Read MoreThis article reports on a detailed gemmological examination of this new synthetic cat's-eye alexandrite.
Read MoreThe author has uncovered many ancient references to the simulation or enhancement of gemstones.
Read MoreThe properties of a novel gemmological imitation, cobalt glass.
Read MoreTwo techniques for identifying natural, treated and synthetic turquoise are examined.
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