slatestone

Etymology

From slate + stone.

slatestone means slate. Lexicurio rates it Sui generis — a strength score of 93 out of 100.

noun

slate“It [St Pinnock Viaduct] has seven piers of roughly-dressed, coursed slatestone from Westwood quarry. […] Moorswater is another masonry replacement, consisting of seven tapering piers of rock-faced slatestone with eight semi-circular arches with granite long and short voussoirs.”