This quarry was until recently still active having started up in 1876. It only closed in 1997 and was known as Tor Quarries. The quarry is fairly large and a huge scar on the landscape as it is seen from the B3357 and the hamlet of Merrivale. The Grimstone and Sortridge leat drops into the quarry basin before starting out again on the other side.
The quarry would have provided granite for New Scotland Yard and Portcullis House, as well as refinishing the stones from the Old London Bridge amongst other buildings and structure around the city of London.
Merrivale Quarry, as it came known to be, continued to be open all the way through to the 1990s, after much quarrying in the 1960s and 1970s, but in the later years actual quarrying stopped and the site was used for finishing imported granite from around the world.
Granite quarried from Merrivale is variously identified as a Giant Granite, Foggintor-Merrivale Granite or a Blue Granite.
The Dartmoor Blue Granite has long been a valued building and ornamental stone as it could be worked with a low risk of fracturing but also had a sufficiently coarse crystalline texture to be decorative.