killas
(ˈkɪləs)
Also 7–9 kellus, 8 killos.
[Cornish.]
The Cornish Miners' term for clay-slate; geologically, the clay-slate of Cornwall, of Devonian age, which rests on the granite.
| 1674–91 Ray Coll. Words Prepar. Metals (E.D.S.) 11 Above the spar lies another kind of substance like a white soft stone, which they call kellus. 1758 Borlase Nat. Hist. Cornwall 92 Round the town of Marazion..there rises a very tender killas, of the cinereous, and also of the yellow colour. 1833 Lyell Princ. Geol. III. 370 At the junction of the granite and killas in St. Michael's Mount. 1875 Geikie Life Murchison I. 301 The Devonshire killas answered in point of geological time to the old Red Sandstone. |
| attrib. 1807 Vancouver Agric. Devon (1813) 11 note, The shillot or killas rock..will always be found accompanied with a similar soil or covering. |