Topaz, aquamarine, and other beryls from Klein Spitzkoppe, Namibia

This article presents, for the first time, both gemological and geologic information on topaz, aquamarine, and other beryls from miarolitic pegmatites at Namibia's historic Klein Spitzkoppe mineral locality. Topaz from Klein Spitzkoppe was first reported more than 100 years ago, in 1889. Many fine specimens have been collected since then, and thousands of carats have been faceted from colorless, transparent "silver" topaz. Gemological investigations of the topaz reveal refractive index values that are somewhat lower, and specific gravity vaines that are slightly higher, than those of topaz from similar deposits. In fact, these values are more appropriate to topaz from rhyolitic deposits than from pegmatites, and apparently correspond to a high fluorine content. The gemological properties of the aquamarine are consistent with known parameters.