‖ grauwacke Geol.
(ˈgraʊvakə)
Also 8 grau-wacken, 9 grawacké, grauwack.
[Ger., f. grau grey + wacke wacke.]
= greywacke.
| 1794 Kirwan Elem. Min. (ed. 2) I. 235 Its [Argillite's] transitions are into..grau-wacken [etc.]. 1806 Davy in Phil. Trans. XCVII. 10 Grauwackè from North Wales. 1828 G. Young Geol. Surv. Yorksh. Coast 55 The hard porphyritic-looking rocks..usually designated by the harsh-sounding name grawacké. 1840 Trans. Geol. Soc. Ser. ii. (1842) VI. 558 The fossiliferous grauwacke which constitutes the chief mountain masses of the right bank of the Rhine. 1876 Smiles Sc. Natur. viii. (ed. 4) 131 The hills, which descend to the coast, are composed of hard grauwacke. |
| attrib. 1832 H. T. De la Beche Geol. Man. (ed. 2) 41 Detritus from the grauwacke slates. 1842 H. Miller O.R. Sandst. ii. (ed. 2) 56 The harder grauwacke schists. 1851 Richardson Geol. viii. (1855) 246 The ancient grauwacke limestones. |