Ferrous and Ferric lons in Synthetic a-Quartz and Natural Amethyst
نویسنده
چکیده
The generation and the removal of the various optical absorption bands in natural amethyst and in synthetic a-quartz doped with either Fe'* or Fe"* ions has been surveyed. Fositive rhombohedral growth regions of synthetic a-qvattz containing Fe'* ion proved to be related to the generation of the amethyst color upon treatment with ionizing radiation. It is believed that the interstitial Fe'* ions in voids perpendicular to positive rhombohedral faces furnish charge compensation for substitutional Fe"* ion. This combination is the precursor of several color centers responsible for the production of the amethyst color.
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