2017:610 - Kilmacshane, Inistioge (Thomastown and Inistioge Water Supply Scheme), Kilkenny

Monitoring was carried out under licence 17E0375 during the construction of the Thomastown and Inistioge Water Supply Scheme. A burnt stone spread was revealed during the monitoring in Kilmacshane townland and excavated under an extension to the same licence in November 2017.

The excavated site lay within the western margin of a large field of rough pasture. Modern houses and their gardens lay to the west beyond a hedged field boundary with a small canalised stream evident in places in a concrete culvert. The natural geological deposits were inclined gently downwards from east to west and were glacial till (clay). Deposits of alluvium and an increased break of slope indicated the former course of the stream. The burnt stone spread had been, in part, dumped or pushed into the margins of this stream.

The burnt stone spread had an irregular shape in plan and measured approximately 12m from south-west to north-east. The deposit occupied the full width of the stripped pipeline wayleave (10m) and was seen to continue to both the north-west and to the south-east outside the area impacted by the development. The burnt stone deposit was composed of loosely compacted, very dark grey to black heat-affected stones typically 0.05m across but occasionally up to 0.1m across. These stones made up perhaps 80% of the deposit with the remainder being black charcoal-rich silt.

The burnt stone spread thickened from the south-east (0.1m or less) to the north-west (0.68m) as the underlying geological deposits dipped down but the upper surface of the burnt stone was approximately level. This reflects the dumping or slumping of the burnt stone into the relict stream edge. Given that the burnt stone was overlain in part by alluvium it is likely that this dumping took place in antiquity and that the area continued to flood after the monument went out of use.

The overlying alluvial deposit that partly sealed the burnt stone spread at its west side comprised loose to moderately compacted light grey silt with occasional small stones.

No trough or pit, as might be expected from similar excavated monuments, was found at Kilmacshane either beneath or adjacent to the burnt stone spread. These features, if present, could lie outside the stripped area.

A radiocarbon determination of Cal. BC 1117-907 (2 sigma) was obtained from the spread (UBA-38052; 2842±39 BP). This date places the monument in the period between the early 12th to early 10th centuries BC – the Late Bronze Age.

Ahish, Ballinruan, Crusheen, Co. Clare