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

The building material here is a close-grained felsite, and huge fragments of it have been used in the construction of the parapets.

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

The lode is a large irregular one of pure arsenical pyrites, existing in a felsite dike near the sea coast.

From Scientific American Supplement, No. 841, February 13, 1892 by Various

Cambrian Period.—In the Pass of Llanberis, along the banks of Llyn Padarn, masses of quartz-porphyry, felsite and agglomerate, or breccia, indicate volcanic action during this stage.

From Volcanoes: Past and Present by Hull, Edward

Some rocks are felsitic in parts but elsewhere glassy; and it is not always clear whether the felsite is an original substance or has arisen by the devitrification of primary glass.

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

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