dacite

Definitions

  • WordNet 3.6
    • n dacite a grey volcanic rock containing plagioclase and quartz and other crystalline minerals
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Century Dictionary and Cyclopedia
    • n dacite A name first used by Fr. Von Hauer and Stache, in 1863, in describing the geology of Transylvania, to include the varieties of greenstone-trachyte which contain quartz. Dacite consists essentially of plagioclase and quartz, together with one or more minerals belonging to the biotite, hornblende, and pyroxene families. The ground-mass is very variable in structure and character. Dacite rarely occurs except in a more or less altered form, and is especially interesting as being one of the rocks associated with occurrences of the precious metals and their ores in Transylvania and the Cordilleran regions of North and South America. It is a rock the composition and classification of which has been the cause of much discussion among geologists. See rhyolite.
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Usage

In literature:

The rocks are liparites, dacites, hornblende and pyroxene andesites.
"Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 2" by Various
Dacite is the lava of Krakatoa and some of the volcanoes of Japan.
"Volcanoes: Past and Present" by Edward Hull
Other dacites, especially augite- and enstatite-dacites, are darker coloured.
"Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 8" by Various
The lavas and ashes ejected by these volcanoes consist of liparite, dacite, andesite and basalt.
"Encyclopaedia Britannica, 11th Edition, Volume 15, Slice 2" by Various
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