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

It is worthy of note that the dykes and sheets of felsite are seldom pierced by the basalt dykes and are probably about the most recent of the intrusive rocks.

From Encyclopaedia Britannica, 11th Edition, Volume 2, Slice 6 "Armour Plates" to "Arundel, Earls of" by Various

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

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)

In the south of the island there are sills and dykes of felsite, quartz-porphyry, rhyolite, trachyte and pitchstone.

From Encyclopaedia Britannica, 11th Edition, Volume 2, Slice 6 "Armour Plates" to "Arundel, Earls of" 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