Min. [ad. L. basaltes, (originally an African word, Pliny), long used in Eng. unchanged.]
1. A kind of trap rock; a greenish- or brownish-black rock, igneous in origin, of compact texture and considerable hardness, composed of augite or hornblende containing titaniferous magnetic iron and crystals of feldspar (labradorite), often lying in columnar strata, as at the Giant’s Causeway in Ireland, and Fingal’s Cave in the Hebrides. (Pliny’s basaltes was probably a variety of Syenite.)
1601. Holland, Pliny, XXXVI. vii. § 11. The Ægyptians also found in Æthyopia another kind of Marble which they call Basaltes, resembling yron as well in colour as hardnes.
1694. Molyneux, Giants Causeway, in Phil. Trans., XVIII. 181. Our Irish Basaltes is composed of Columns.
1789. Mrs. Piozzi, Journ. France, II. 364. Its composition seemed black basalt.
1813. Sir H. Davy, Agric. Chem., iv. 195. Basalt or whinstone.
1837. W. Irving, Capt. Bonneville (1849), 317. Prismoids of basaltes, rising to the height of fifty or sixty feet.
1845. Darwin, Voy. Nat., ix. (1852), 180. The Basalt is only Lava, which has flowed beneath the sea.
b. attrib. and in comb., as in basalt rock, -building.
1769. Raspe, in Phil. Trans., LXI. 580. Our basalt rocks differ from those of the Giant’s Causeway.
1873. Tristram, Moab, ix. 174. The basalt-building inhabitants.
2. A black porcelain invented by Wedgwood.
1832. G. Porter, Porcelain, 17. Basaltes, or black ware … was a black porcelainous biscuit, having nearly the same properties as the natural stone.
