<P> The most significant is that of Cornwall and Devon where the Delabole Quarry is thought to be the largest single quarry in the island . Many of these are no longer worked owing to lower costs of extraction in the larger British workings . The quarrying of slate in Cornwall is known to have been carried out from the late mediaeval period and there was a considerable export trade from some of the quarries near the coasts in the 19th century . </P>
<P> The most significant is that of Cornwall and Devon where the Delabole Quarry is thought to be the largest single quarry in the island . Many of these are no longer worked owing to lower costs of extraction in the larger British workings . The quarrying of slate in Cornwall is known to have been carried out from the late mediaeval period and there was a considerable export trade from some of the quarries near the coasts in the 19th century . </P>
where does slate come from in the uk
where does slate come from in the uk
Cornwall Devon
Cornwall Devon