| Gemstones have a long, and occasionally ‘jaded’ history. Since prehistoric times, precious gems have been used in barter, for decorations, and in rituals; the key to their value being in their beauty. For instance, a jade bangle with an interior diameter of 49.50 mm and 8.36 mm thickness sold for $2,576,600 in 1999. The obvious problem of determining gemstone value is that the character of it can be enhanced (or even produced ab initio) by unnatural methods. In cases where enhancement is disclosed this is not an issue. Fraud is, however, a major concern when enhancements are not disclosed.
There are three classes of jadeite jade now commonly available. “A” grade jade is totally natural (jadeite), “B” has been treated (as discussed in the note), and “C” has been artificially color-enhanced. Typically, “C” jade is fairly easy to spot, but the treatments applied to “B” materials are more subtle. FT-IR spectroscopy provides an excellent tool for analyzing “A” and “B” jade. Signals due to the wax or epoxy resin are quite definitive.
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