hornfels

American  

[hawrn-felz] / ˈhɔrn fɛlz /

noun

1. a dark, fine-grained metamorphic rock, the result of recrystallization of siliceous or argillaceous sediments by contact metamorphism.

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hornfels British  

/ ˈhɔːnfɛlz /

noun

1. Also called: hornstone.  a hard compact fine-grained metamorphic rock formed by the action of heat from a magmatic intrusion on neighbouring sedimentary rocks

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hornfels Scientific  

/ hôrn′fĕlz′ /

1. A fine-grained metamorphic rock having a uniform grain size and formed by contact metamorphism.

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Etymology

Origin of hornfels

1850–55; < German, equivalent to Horn horn + Fels rock, cliff

Example Sentences

Crystals in hornfels grow smaller with metamorphism and become so small that specialized study is required to identify them.

From Textbooks • Jan. 1, 2017

The lowest pressure conditions produce hornfels facies, while higher pressure creates greenschist, amphibolite, or granulite facies.

From Textbooks • Jan. 1, 2017

Fine-grained shale and basalt, which happen to be chemically similar, characteristically recrystallize to produce hornfels.

From Textbooks • Jan. 1, 2017

Mudrock or volcanic rock will be converted to hornfels.

From Textbooks • Jan. 1, 2015

From diabases, basalts, andesites and other igneous rocks a third type of hornfels is produced.

From Encyclopaedia Britannica, 11th Edition, Volume 13, Slice 6 "Home, Daniel" to "Hortensius, Quintus" by Various