A look at the artistic heritage of the Drehers, an influential family of gem carvers in Idar-Oberstein, Germany.
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An introduction to Moroccan amethyst, which features distinctive color zoning and inclusions.
Read MoreFor more than a century, the Four Peaks mine in Maricopa County, Arizona, has produced gem-quality amethyst.
Read MoreThe proper use and limitations of IR spectroscopy for identifying natural versus synthetic amethyst of various types have been investigated, focusing on the region 3800–3000 cm-1.
Read MoreBrazil is currently the leader in overall production of amethyst.
Read MoreWhere there are no inclusions or colour zoning, the presence of Brazil twinning in the natural amethyst will usually make the distinction.
Read More"Damsonite," the trade name for a new type of chalcedony, is analysed and described.
Read MoreAn overview of the plentiful and various gem materials being discovered and produced in Afghanistan.
Read MoreA new and rather unusual gem material and possible treatments are discussed.
Read MoreWhen microscopic identification is not feasible, FTIR spectra at high resolution (0.5 cm–1) can distinguish natural and synthetic amethyst.
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