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

Felsite, fel′sīt, n. a fine-grained, compact rock, a variety of quartz-porphyry—also Fel′stone.—adj.

From Project Gutenberg

Felspar in Colorado and felsite magnesian slate in Newfoundland carry gold.

From Project Gutenberg

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 Project Gutenberg

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 Project Gutenberg

Although there are few objections to the employment of felsite as a field designation for rocks having the above characters, it lacks definiteness, and has been discarded by many petrologists as unsuited for the exact description of rocks, especially when their microscopic characters are taken into consideration.

From Project Gutenberg