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 designs were rudely pecked on the moderately smooth felsite cliffs on a nearly perpendicular wall in the foot-hills, about forty feet above the bed of the arroyo, or gulch.

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

It exists in a felsite dyke immediately on the coast.

From Getting Gold: a practical treatise for prospectors, miners and students by Johnson, J. C. F. (Joseph Colin Frances)

Other hard rocks such as chert, quartzite, felsite, granite, sandstone and volcanic rocks very frequently are largely represented in gravels, while coal, limestone and shale are far less common.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 4 "Grasshopper" to "Greek Language" 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

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