felsite

American  

[fel-sahyt] / ˈfɛl saɪt /

noun

1. a dense, fine-grained, igneous rock consisting typically of feldspar and quartz, both of which may appear as phenocrysts.

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felsite British  

/ fɛlˈsɪtɪk, ˈfɛlsaɪt, ˈfɛlˌstəʊn /

noun

1. any fine-grained igneous rock consisting essentially of quartz and feldspar

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felsite Scientific  

/ fĕl′sīt′ /

1. A fine-grained, light-colored igneous rock, consisting mainly of feldspar and quartz.

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Other Word Forms

• felsitic
  adjective

Etymology

Origin of felsite

First recorded in 1785–95; fels(par) + -ite ¹

Example Sentences

From this place to the mines the rocks were soft decomposing dolerites, with many harder bands of felsite, and, occasionally, plains composed of more recent trachytic lavas.

From The Naturalist in Nicaragua by Belt, Thomas

But felsite or microfelsite is still the generally accepted designation for that very fine-grained, almost crypto-crystalline substance which forms the ground-mass of so many rhyolites, dacites and porphyries.

From Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 2 "Fairbanks, Erastus" to "Fens" by Various

The stones themselves were felsite, which abounds in the locality.

From Unknown Mexico, Volume 1 (of 2) A Record of Five Years' Exploration Among the Tribes of the Western Sierra Madre; In the Tierra Caliente of Tepic and Jalisco; and Among the Tarascos of Michoacan by Lumholtz, Carl

Rock of many kinds, including serpentine, schist, felsite, jadeite, diorite, and nephrite, were used; and saws of flint or chalcedony, some toothed on one side only, others on both, are of frequent occurrence.

From Manners and Monuments of Prehistoric Peoples by D'Anvers, N.

These rocks approach towards true granites in one direction, and through quartz-porphyry and felsite to rhyolite in another—probably depending upon the conditions of cooling and consolidation.

From Volcanoes: Past and Present by Hull, Edward