In 1791 74 families were living in the village, and 322 men were employed in the quarry. In 1845 there were 300 men employed in the quarry, with average wages of about 12 shillings a week. The height of the quarry was then about 200 feet, and it was about 500 feet long. The first level was 30 feet above the high tide mark. By 1955 it was 280 feet from the top of the quarry to the road level, and 130 feet to the lowest part (below the road level). There were 11.5 miles of railroad for wagons drawn by 12 horses. There were 12 stationary engines and one locomotive.

Ballachulish slate was shipped to England, Ireland, and even America. Boats came into a quay at Ballachulish, and were loaded by the workers passing the slates by hand over a plank between the shore and the boat. In 1825 26 million slates were made and shipped out of Ballachulish.

In 1951 only about 20 men were still employed in the quarry, producing about a million slates annually. The quarry was finally closed in 1955.