buhrstone

[ bur-stohn ]

noun

1. a variant of burstone.

buhrstone

/ ˈbɜːˌstəʊn /

noun

1. a hard tough rock containing silica, fossils, and cavities, formerly used as a grindstone
2. a grindstone or millstone made of this rock

Word History and Origins

Origin of buhrstone¹

C18 burr , perhaps identical to burr ¹(alluding to roughness)