Initially, the building stone used at Auchindrain came from the glacial till in and around the Township itself. This would have been the stone gathered up and set aside during the first clearance of the fields, and then stone ploughed up in the course of cultivation or excavation. It consists of boulders rounded by the action of ice and water, and has a very characteristic appearance.
At some point, the naturally-available supply of this stone was clearly exhausted, and it was then necessary for the township to obtain further supplies from elsewhere. In the South Field, the bedrock lies relatively close to the surface, whilst the natural landform provided a steep face immediately adjacent to the original line of the main road. A small quarry was then opened here: this is likely to have been after 1871, because it is not marked on the First Edition Ordnance Survey surveyed that year. The Township’s population at the time included at least one person, Neil McGugan, who was familiar with the techniques and technology involved in quarrying – in the 1860s and maybe before, he was employed as a miner at Craignure nickel and copper mine nearby, where he would have have learned skills such as drilling and blasting.
The quarry is fenced around its east, south and west sides, to secure it from stock grazing in the South Field: the metal fencing materials are the same as those used along the side of the main road, and may have been erected at the same time. It is not known when the Quarry was last worked.