Caracterización mineralógica de algunos topacios españoles.

Abstract

Deposits and principal physico-cemical characteristics of some Spanish topazes are described. From the chemical point of view it is to be noted the high fluorine content (18.9--20.32%) of these topazes, that can be correlated well with other physical properties and to be related with the high fluorine percentages of the paragenesis. Topazes occur in pegmatite, greisen and hydrothermal deposits, usually with fluorite. The outcrops studied present a limited amount of topaz, but from two of them (Valle de la Serena and Merida) beautiful faceted gemstones can be obtained of a transparency, low fracturing and feeble blue-green coloration very suitable.