hornstone

American  

[hawrn-stohn] / ˈhɔrnˌstoʊn /

noun

Archaic.

1. a variety of quartz resembling flint.

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hornstone British  

/ ˈhɔːnˌstəʊn /

noun

1. another name for chert hornfels

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Etymology

Origin of hornstone

1720–30; translation of German Hornstein

Example Sentences

The shales become dense, highly crystalline rocks of a "hornstone" type, with porphyritic developments of silicate minerals.

From The Economic Aspect of Geology by Leith, C. K. (Charles Kenneth)

Masses, and in some instances nodules, of hornstone, resembling true flint, are found imbedded in it; yet it is not to be confounded with the chalk formation.

From Scenes and Andventures in the Semi-Alpine Region of the Ozark Mountains of Missouri and Arkansas by Schoolcraft, Henry Rowe

Above this, constituting the top layer, or surface soil, rests a bed of diluvial materials, filled with broken-down fragments of rock, masses of radiated quartz, and chips of hornstone.

From Scenes and Andventures in the Semi-Alpine Region of the Ozark Mountains of Missouri and Arkansas by Schoolcraft, Henry Rowe

Another of the dikes of the north-east of Ireland has converted a mass of red sandstone into hornstone.

From The Student's Elements of Geology by Lyell, Charles, Sir

The porphyry has a compact basis, like hornstone, of a dull brown colour, which contains imbedded crystals of felspar and quartz, and occasionally of augite.

From Narrative of a Second Expedition to the Shores of the Polar Sea by Franklin, John