firestone
nounEtymology From Middle English firestone, firstan, fyrestane, fyyr stone, from Old English fȳrstān, equivalent to fire + stone.
1
Iron pyrite, formerly used for striking fire.
2
A flint.
3
A heat-resistant stone that will withstand intense heat of a furnace, used for lining kilns, campfire rings, fireplaces and furnaces; especially, the sandstone at the top of the upper greensand in the south of England.
- On the descent the line is often in cuttings; some are high, such as at Scarcroft, where a cut through firestone and fireclay was necessary, and near Bardsey, where the line threads a deep tree-lined gorge.1961 February, D. Bertram, “The lines to Wetherby and their traffic”, in Trains Illustrated, page 101: