Part of the main copper mining complex, this is a small building with its western half built up on a platformed area approx. 0.7m high. Located only 3m north of a mine shaft, it has a large opening to the east and a possible window facing south. Walls remain up to a height of 1.8m and the overall measurements for the structure are 5m east/west by 6m north/south. There is a large gravel pile in the south-west corner of the building. Noted during an upland survey conducted by Archaeophysica during 2005-6