Standing building survey and desk-based assessment was undertaken in September of last year by staff from CFA Archaeology Ltd on two farms proposed for removal in advance of an expansion to the Greenburn Surface Mine. Building survey suggested that the oldest surviving structures at both Wellhill and Hall of Auchincross were likely to date to the late 18th and early 19th century. However, cartographic analysis suggested that both had origins before this period. Wellhill appeared on Blaeu's 1654 atlas of Scotland, where it was annotated as 'Welhil', and later appeared on Roy's 1752-55 Military map as a collection of dispersed buildings. The earliest named appearance of Hall of Auchincross was also on Blaeu's 1654 atlas, which depicted 'Midle Auchencorfs' at the location of the farm. Below this placename, a circular pale enclosing trees and a building was depicted. As with Wellhill, Auchincross was depicted as a collection of dispersed buildings on Roy's 1752-55 Military map, on which it was identified as 'Haw of Auchincourse'. The 1857 First Edition Ordnance Survey map depicted Hall of Auchincross farm with a courtyard arrangement of buildings with a rectilinear building with two wings at the north-west and south-east ends. On the north-west side of the farm was written 'Site of Old Hall', while on its east side the 'site of Court Knowe' was shown.
These features were described in the Ordnance Survey Object Name Book of 1856, which stated that the old hall stood to the north-west of the farmhouse, and that it was said to have been a 'very ancient place'. When visited by the Ordnance Survey in 1981, the published site of the hall was recorded as lying below modern farm buildings, but it was noted that placed high in the NW gable end of a late farm building was a carved stone face and a lintel stone bearing the initials G C and B C. The Name Book recorded that there was formerly a court knowe near the Hall of Auchincross, on which criminals are said to have been tried by the laird of Auchincross. The tradition that this served as a court mound supports the suggestion that Hall of Auchincross was not only a laird's dwelling, but also the administrative centre of the estate.
Building survey identified the architectural fragments previously recorded by the Ordnance Survey. Built into the fabric of the primary construction of the byre and calving shed was a door lintel with roll moulding containing the initials GC-BC, situated on either side of a heraldic shield embossed with three stars. On the right-hand side of the carved lintel, and built within the fabric used to increase the height of the gable, was a carved face on a stone corbel. Below the carved head were a series of five moulded sill stones built on top of each other, all having been incorporated into the fabric of heightening work. The architectural character of the lintel with initials and the carved face places them in the 16th century, and in all probability they have originated from the earlier medieval hall that occupied the site of the present farm complex