A form of sedimentary rock, similar to sandstone but coarser.(noun)
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Use "gritstone" in a sentence
"Germoe till last century, when they were broken up for road-metal, and that they consisted of a kind of gritstone common enough to the Crowza"
"A buzzard cried somewhere beyond Hayes Farm; otherwise there was no sign of animal life in all that windswept country below the crest of the western gritstone uplands."
"Geographically it is part of the Pennine range and its gritstone fells and sweeping heather moorland are perfect for gentle walks."