Monument record 2657/3/6 - Late Iron Age ironworking, Priors Hall

A late Iron Age iron working site was identified during archaeological investigation. A total of nine furnaces were found, comprising one bowl furnace, seven shaft furnaces and one D-shaped furnace. One of the furnaces had an associated structure, possibly a wind break or smithy. There was limited evidence of charcoal production.

{2} A likely iron smelting site was identified in Trench 9, sited to pick up on geophysical anomalies identified earlier. Excavation was restricted by the depth at which deposits occurred beneath the current ground surface.
A large amount of iron slag (including tap slag), charcoal and fired clay was identified in the base of the trench. In the north-eastern corner of the trench this deposit became much more dense, with possible fragments of in-situ furnace observed.
The industrial deposits were sealed by a layer of clayey silt from which a single sherd of possible Saxon pottery was recovered.
Immediately to the north-east of the trench is a mound which may be associated with the smelting site eg.a possible dump of waste material.

{4} Nine individual smelting furnaces were identitied during excavations at Priors Hall. The simplest in form is the bowl furnace type which located on the crest of a shallow south-facing slope in Area 1. It is distinct from the other furnaces at Priors Hall which are mostly of the sunken shaft type. A single D-shaped furnace was also identified.
The bowl furnace is located towards the centre of a small complex of related structures, including a cigar-shaped pit to the south, filled with slag and fired clay and a system of narrow, shallow gullies.
It is possible that the gullies may represent the remains of a wind break protecting the furnace, but if so the presence of the gully to the east would probably have hindered access to the most likely location for the extraction of iron and cleaning of the furnace.
Four furnaces (Furnaces, 2, 3a, 3b and 4) are all sited on the 87.52m OD contour of the south facing slope and all located within 50m of each other. All are of shaft type, varying in degrees of preservation from excellent to moderate.
The most easterly of the group of shaft furnaces was the only furnace to be associated with a structure.
Initially a pit with a rounded base was excavated, within which the clay furnace shaft structure was built.
Both tapping pit and shaft were backfilled with debris from the decommissioned furnace. Late Iron Age grog and shell tempered wares were recovered from the backfill of the tapping pit, along with two small intrusive sherds of Romano-British grey ware.
The northern side of the furnace was enclosed by an elongated C-shaped steep-sided sill beam trench, the north-eastern corner of which was demarcated by a large post pit. This presumably represents the remains of a three-sided structure, possibly providing shelter to the centrally positioned furnace. An isolated posthole to the south of the furnace may also have formed part of the structural complex.

Further excavations undertaken during stripping of the access road revealed three more furnaces at the southern limit of the site. These fall just outside what appears to be the northern boundary for the villa complex in the lower reaches of the valley side.
Furnace 6 was the most westerly of the group of three shaft furnaces, was the most complete, and along with Furnace 7 offers a rare stratigraphic relationship as two burials clearly truncate the tapping pit .
Both shaft and tapping pit are filled with decommissioned furnace debris comprising fired clay and slag. Several sherds of late Iron Age pottery were recovered form the tapping pit and the backfill of the shaft.
Like Furnace 6, the tapping pit of Furnace 7 has been truncated by a later burial.
Furnace 8 broadly followed the same construction model as those recorded elsewhere.
Archaeomagnetic dating was undertaken, but was largely unsuccessful.

<1> Shiel D.; Robertson F., 2004, Priors Hall, Corby: Geophysical Survey Report, p.10 (checked) (Report). SNN105488.

<2> Hall R.V., 2006, Archaeological Evaluation on Land at Priors Hall, Corby, Northamptonshire (CPH06), p.3-4 (checked) (Report). SNN105632.

<3> Hall R.V., 2006, Archaeological Evaluation of Blocks 2 & 3, Zone 1, Priors Hall, Corby, Northamptonshire (CPHB06), p.4+fig.11 (checked) (Report). SNN105853.

<4> Hall R., 2008, Excavations at Priors Hall, Northamptonshire, 2006: An Iron Age and Romano-British Ironworking Complex, p.28 (checked) (Report). SNN106586.

Record last edited

Dec 13 2022 10:26AM