West Laroch slate quarries, Ballachulish slate belt, Scotland

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From: Richey, J.E. and Anderson, J.G.C. 1944. Scottish slates. Wartime pamphlet No. 40. London : Geological Survey of Great Britain.

West Laroch[edit]

Map of the Ballachulish slate belts. P519817.


One inch to the mile (Geological: colour-printed) Sheet 53

Six inches to the mile Argyll, Sheet 30 S.E.

General description[edit]

The Ballachulish Slates form an outcrop about half a mile wide at Wet Laroch. This outcrop extends southwards up a steep hill-slope, but narrows and finally ends about 1¼ mls, from the shore. Near the coast it has been worked in two openings, now disused, termed the West Quarry and the Middle Quarry.

West Quarry[edit]

Locality On W. side of West Laroch.
Access Adjacent to main road, railway and coast
Description of slate Colour dark grey, surface even, texture medium. Pyrites (‘diamonds’) fairly abundant and of moderate size (average ¼ inch diameter).
Dips, with amounts Cleavage-dip E. 21º S. at 80º. Bedding coincident or almost coincident with cleavage.
Joints No general direction of joints, which are moderately abundant, was noted.

Details of workings[edit]

About half the face, which is fully 100 ft. in height, is more or less obscured by debris, while a considerable thickness near the top is much shattered and bent. Sink, 40 ft, deep, is filled with debris. About four seams each containing some 10 to 15 ft. of good slate, are said to have been worked. On the E. side brown limy bands occur and tend to increase to S. Overburden, consisting of clayey morainic, is relatively moderate on the steep slope to S. of the quarry.


Large reserved exist to S., but their working is regarded as difficult owing to the steep slope covered with overburden, and difficulty of keeping surface water off the face in winter.

Middle Quarry[edit]

Locality Just E. of West Quarry.
Access Adjacent to main road, railway and coast.
Description of slate As for West Quarry
Dips, with amounts Cleavage-dip E. 11º S. at 70º. Bedding-dip, noted near centre of quarry, S. 30ºW. at 45º.
Joints As for West Quarry.

Details of workings[edit]

A considerable proportion of the workings is under water, above which there is a face about 100 ft, in height, the lower part of which is covered in debris. Two major seams, totally 30 ft., are said to have been worked. Near the centre of the face there is a 3-ft dyke of dark whin (lamprophyre) running N. 150º W. obliquely across the face.