Feature

A New Method for Imitating Asterism

Shane F. McClure(谢恩·F.·麦克卢尔), John I. Koivula(约翰· I.·科伊武拉)

Several gems were recently examined that showed stars with an unnatural appearance or an unusual number of rays. Asterism in some of these gem materials is very rare, or has not been seen previously by the authors. Microscopic examination revealed that these “stars” were produced by using what appeared to be a rough polish to scratch lines in an oriented fashion onto the upper surface of the cabochons.

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