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Evidence for iron-making activities of probable Roman age close to the outcrop of a major iron-ore body were revealed during development. Excavation was undertaken, by permission of LAW, of a small (approximately 14m x 2m) undisturbed area, bounded to the north by a quarry and in other directions by disturbed ground. The excavated area lay on the southern margin of a low hill of limestone bedrock (now largely quarried away), overlain by boulder clay to the south and lay approximately 200m south of the former outcrop of the iron ores exploited in the 19th century by the Bute Mine.
The site comprised a discontinuous dark slag-rich deposit up to 20 cm thick, resting on subsoil, or directly on the irregular karstic surface of the limestone, and interpreted as a series of small slag dumps, 1 - 2m diameter. The site has yielded in excess of 0.5t of stratified slag, despite the very small area. The majority of the dumps were almost entirely of smelting slags, dominated by tapped material. One dump towards the west of the site was dominated by smithing, probably bloom-smithing, cakes. The only stratified artefactual material were a few, relatively unabraded and conjoining sherds of Oxfordshire ware from the deposit of smithing cakes, tentatively suggesting a late Roman date (3rd - 4th century) for the iron making operations. The slag dumps appear to have been little disturbed by later activity, but their upper surfaces yielded much 19th - 20th century debris, including china and a table knife. Two small sherds of calcite-tempered pottery tentatively dated to 12th century were also found, but from a context disturbed by machinery. This medieval pottery is interpreted as probably associated with the superficial material, rather than being stratified within the iron-making residues, but some caution must be exhibited in dating the site on such slim evidence.
Excavated material was sieved at 1cm and all slag above this grade was recovered. Spot samples were taken for investigation of finer residues. It is hoped that analysis of this large body of slag will reveal details of the smelting and bloom-smithing processes, even in the absence of structural remains of hearths or furnaces. Preliminary results show a surprising diversity of tapping techniques, with flows variously onto charcoal, stone and clay surfaces. Total slag production per smelt appears to have been approximately 5 - 8kg. Smithing cakes are variable in size, but are typically 2 - 3kg. Such slag volumes are consistent with other known Roman smelting operations in the Bristol Channel Orefield. The slag dumps also yielded quantities of ore. Some fragments of which are probably accidental losses, but much appears to have been deliberately rejected as being too siliceous.
The field to the east of the excavated site remains undisturbed, but is also threatened by development. A programme of geophysical surveys (centre approximately ST0530 8145) was therefore undertaken to determine whether the site extended in this direction. No evidence was found, however, to suggest archaeological features in this area.