Iron Age iron smelting, Folly Court, Wokingham and the interpretation of 'dome' furnaces
##plugins.themes.bootstrap3.article.main##
##plugins.themes.bootstrap3.article.sidebar##
Published
Apr 2, 2025
Tim Young
https://orcid.org/0000-0002-0275-7686
George Anelay
https://orcid.org/0000-0002-0275-7686
George Anelay
Abstract
Excavations produced evidence for a Middle Iron Age iron smelting centre, probably of the 2nd century BC, with four iron smelting furnaces, three of a large ‘dome’ morphology and one smaller, more conventional, slagpit-type. A total of over 800 kg of slag was recovered from the site, indicating an operation of some significance. Details of furnace construction and large suites of archaeometallurgical residues were recovered for two successive examples of the ‘dome’ furnaces. ‘Dome’ furnaces are rare and poorly known from the British Iron Age, although common in parts of Europe. New evidence shows that they may have been operated on a continuum with smaller furnace types. Precise interpretation was hampered by ambiguities within the compositional modelling, but these furnaces both illustrate the sophistication of Iron Age iron smelting in Britain and demonstrate the need for its more nuanced and evidence-driven interpretation.
##plugins.themes.bootstrap3.article.details##
Keywords
iron smelting, dome furnace, Iron Age
References
Allen, M., Young, T., Simmonds, A. and Champness, C. (2018). A Roman enclosed settlement with evidence for early medieval Iron smelting at Staveley Lane, Eckington, The Derbyshire Archaeological Journal 138, 61–91.
Boesenberg, J. S. and Hewins, R. H. (2010). An experimental investigation into the metastable formation of phosphoran olivine and pyroxene, Geochimica et Cosmochimica Acta 74, 1923–1941. doi: 10.1016/j.gca.2009.12.008
Crew, P. (1987). Bryn y Castell hillfort – a late prehistoric iron working settlement in north-west Wales. In Scott, B. G. and Cleere, H (Eds.) The crafts of the blacksmith. Essays presented to R.F. Tylecote at the 1984 Symposium of the UISPP Comité pour la sidérurgie ancienne held in Belfast, N. Ireland, 16th-21st September 1984 (pp. 91–100). Belfast: UISPP Comité.
Crew, P. (1989). Crawcwellt West excavations 1986- 1989. A late prehistoric ironworking settlement, Archaeology in Wales 29, 11–16.
Crew, P. (1991). The experimental production of prehistoric bar iron, Historical Metallurgy 25, 21–36.
Crew, P. (1998). Excavations at Crawcwellt West, Merioneth, 1990-98. A late prehistoric upland ironworking settlement, Archaeology in Wales 38, 22–35.
Crew, P. (2009). Iron working in Merioneth from prehistory to the 18th century. Maentwrog: Plas Tan y Bwlch (Darlithiau Coffa Merfyn Williams Memorial Lectures No. 2).
Crew, P. (2013). Twenty-five years of bloomery experiments: perspectives and prospects. In D. Dungworth and R.C.P. Doolan (Eds.), Accidental and experimental archaeometallurgy (pp. 25–50). London: Historical Metallurgy Society (HMS Occasional Publication No 7).
Evenstad, O. (1790). Afhandling om jern-malm, som finds i Myrer og Moradser i Norge, og omgangsmaaden med at forvandle den til jern og staal. Et priisskrift, som vandt det Kongelige Landhuusholdnings-Selskabs 2den Guldmedaille, i Aaret 1782. Det Kongelige Danske Landhuusholdnings-selskabs Skrifter D.3, 387–449.
Every, R. and Mepham, L. (2006). Prehistoric pottery. In J. Lewis, F. Brown, A. Batt, N. Cooke, J. Barrett, R. Every, L. Mepham, K. Brown, K. Cramp, A.J. Lawson, F. Roe, S. Allen, D. Petts, J. McKinley, W. Carruthers, D. Challinor, P. Wiltshire, M. Robinson, H. Lewis, M. Bates, K. Nichols and E. James (Eds), Landscape Evolution in the Middle Thames Valley Heathrow Terminal 5 Excavations Volume 1 (CD-ROM, 1). Oxford: Perry Oaks Framework Archaeology Monograph No. 1.
Garner, J. (2010a). Der Siegerländer Kuppelofen im europäischen Vergleich, Siegerland 87, 174–197.
Garner, J. (2010b). Der latènezeitliche Verhüttungsplatz in Siegen-Niederschelden „Wartestraße“, Metalla 17, 1–147.
Grimes, W.F. and Close-Brooks, J. (1993). The excavation of Caesar’s Camp. Heathrow, Harmondsworth, Middlesex, 1944, Proceedings of the Prehistoric Society 59, 303–360. doi: 10.1017/S0079497X00003832
Hardy, A. and Young, T.P. (2019). Iron Age smelting and medieval charcoal production at Fleet Hill Farm, Eversley Quarry, Finchampstead, Wokingham. Archaeological investigations in 2009-2011, Berkshire Archaeological Journal 84, 43–65.
Jensen, N.L. (1968). A treatise on iron ore as found in the bogs and swamps of Norway and the process of turning it into iron and steel, Abridged translation of Evenstad 1790, Bulletin of the Historical Metallurgy Group 2, 61–65.
Lewis, J., Crabb, S. and, Ford, S. (2013). Bronze Age urns, Iron Age iron smelting and Saxon charcoal production at Sadler’s End, Sindlesham, Wokingham, Berkshire. In S. Preston (Ed.) Iron Age production sites in Berkshire, Excavations 2003 – 2012 (pp. 1–34). Reading: Thames Valley Archaeological Services (Monograph 16).
Natural England (2010). England’s peatlands; carbon storage and greenhouse gases. York: Natural England (Natural England Report 257).
Paynter, S. (2002). Iron-working slag. In A. Holmes (Ed.), Clearwell Quarry Extension, Stowe Hill, Gloucestershire (pp. 6–7). Oxford: Oxford Archaeology (unpublished report).
Paynter, S. (2007). Innovations in bloomery smelting in Iron Age and Romano-British England. In S. La Niece, D. Hook and P. Craddock (Eds.), Metals and Mines. Studies in Archaeometallurgy (pp. 202–210). London: Archetype Publications in association with the British Museum.
Paynter, S., Crew P., Blakelock, E. and Hatton, G. (2015). Spinel-rich slag and slag inclusions from a bloomery smelting and smithing experiment with a sideritic ore, Historical Metallurgy 49, 126–143.
Sauder, L. (2013). An American bloomery in Sussex. In D. Dungworth and R.C.P. Doolan (Eds.), Accidental and experimental archaeometallurgy (pp. 69–74). London: Historical Metallurgy Society (HMS Occasional Publication No 7).
Seager Thomas, M. (2010). A re-contextualisation of the prehistoric pottery from the Surrey hillforts of Hascombe, Holmbury and Anstiebury, Surrey Archaeological Collections 95, 1–33.
Smart, C., Young, T., Allan, J., Dawson, D., Taylor, R.T., Andersen, J., Rollinson, G., Challinor, D., Jones, J., Marshall, P., Tompkins, M., Collings, T., Keen, O., Bronk Ramsey, C., Dunbar, E. and Reimar, P. (2018). Industry and the making of a rural landscape: iron and pottery production at Churchill’s Farm, Hemyock, Devon. Oxford: BAR Publishing (BAR British Series 636). doi: 10.30861/9781407316260
Stöllner, T. (2014). The Siegerland as an iron production area during the first millennium BC: a regional approach to a famous mining region. In B. Cech and Th. Rehren (Eds.), Early Iron in Europe (pp. 43–64). Montagnac: Instrumenten Europe (Monographies Instrumentum 50).
Wagner, D.B. (1990). Ancient carburisation of iron to steel: a comment, Archeomaterials 4, 111–117.
West Sussex Archaeology (2014a). Archaeological Assessment and Written Scheme of Investigation for Archaeological Works at Folly Court, Barkham Road, Wokingham, Berkshire. Petersfield: West Sussex Archaeology (unpublished report).
West Sussex Archaeology (2014b). Written Scheme of Investigation for Archaeological Works at Folly Court, Barkham Road, Wokingham, Berkshire. Petersfield: West Sussex Archaeology (unpublished report).
West Sussex Archaeology (2018). Report on Archaeological Works at Folly Court, Barkham Road, Wokingham, Berkshire. Petersfield: West Sussex Archaeology (unpublished report).
Young, T.P. (2011). Some preliminary observations on hammerscale and its implications for understanding welding, Historical Metallurgy 45, 26–41.
Young, T.P. (2015a). Assessment of archaeometallurgical residues from Truro EDC. Caerphilly: GeoArch (Report 2015-13).
Young, T.P. (2015b). Assessment of archaeometallurgical residues from Yorkley, Gloucestershire. Caerphilly: GeoArch (Report 2015-24).
Young, T.P. (2016a). Archaeometallurgical residues from Tolgarrick Farm, Truro, Cornwall. Caerphilly: GeoArch (Report 2016-19).
Young, T.P. (2016b). Archaeometallurgical residues from Fleet Hill Farm, Finchampstead, Berkshire. Caerphilly: GeoArch (Report 2016/35).
Young, T.P. (2016c). Ironworking residues from Tregurra, Truro, Cornwall. Caerphilly: GeoArch (Report 2016/38).
Young, T.P. (2018a). Archaeometallurgical residues from Folly Court, Wokingham, Berkshire. Caerphilly: GeoArch (Report 2018/15).
Young, T.P. (2018b). Assessment of archaeometallurgical residues from Lockleaze (Ding Crusaders). Caerphilly: GeoArch (Report 2018/24).
Young, T.P. (2020). Archaeometallurgical residues from Hartshill Copse (HCB01). Caerphilly: GeoArch (Report 2020/17).
Young, T.P. (2022a). Archaeometallurgical residues from Bexhill. Caerphilly: GeoArch (Report 2022/09).
Young, T.P. (2022b). Chapter 7. Archaeometallurgy. In S.R. Taylor (Ed.), Down the bright stream: the prehistory of Woodcock Corner and the Tregurra Valley, Cornwall (pp. 170–204). Oxford: Archaeopress. doi: 10.2307/j.ctv2nwq8zn.15
Young, T.P. and Hart, R. (2021). The refining process (2): new data from Ynysfach Ironworks, Merthyr Tydfil, Historical Metallurgy 51(1), 34–50.
Boesenberg, J. S. and Hewins, R. H. (2010). An experimental investigation into the metastable formation of phosphoran olivine and pyroxene, Geochimica et Cosmochimica Acta 74, 1923–1941. doi: 10.1016/j.gca.2009.12.008
Crew, P. (1987). Bryn y Castell hillfort – a late prehistoric iron working settlement in north-west Wales. In Scott, B. G. and Cleere, H (Eds.) The crafts of the blacksmith. Essays presented to R.F. Tylecote at the 1984 Symposium of the UISPP Comité pour la sidérurgie ancienne held in Belfast, N. Ireland, 16th-21st September 1984 (pp. 91–100). Belfast: UISPP Comité.
Crew, P. (1989). Crawcwellt West excavations 1986- 1989. A late prehistoric ironworking settlement, Archaeology in Wales 29, 11–16.
Crew, P. (1991). The experimental production of prehistoric bar iron, Historical Metallurgy 25, 21–36.
Crew, P. (1998). Excavations at Crawcwellt West, Merioneth, 1990-98. A late prehistoric upland ironworking settlement, Archaeology in Wales 38, 22–35.
Crew, P. (2009). Iron working in Merioneth from prehistory to the 18th century. Maentwrog: Plas Tan y Bwlch (Darlithiau Coffa Merfyn Williams Memorial Lectures No. 2).
Crew, P. (2013). Twenty-five years of bloomery experiments: perspectives and prospects. In D. Dungworth and R.C.P. Doolan (Eds.), Accidental and experimental archaeometallurgy (pp. 25–50). London: Historical Metallurgy Society (HMS Occasional Publication No 7).
Evenstad, O. (1790). Afhandling om jern-malm, som finds i Myrer og Moradser i Norge, og omgangsmaaden med at forvandle den til jern og staal. Et priisskrift, som vandt det Kongelige Landhuusholdnings-Selskabs 2den Guldmedaille, i Aaret 1782. Det Kongelige Danske Landhuusholdnings-selskabs Skrifter D.3, 387–449.
Every, R. and Mepham, L. (2006). Prehistoric pottery. In J. Lewis, F. Brown, A. Batt, N. Cooke, J. Barrett, R. Every, L. Mepham, K. Brown, K. Cramp, A.J. Lawson, F. Roe, S. Allen, D. Petts, J. McKinley, W. Carruthers, D. Challinor, P. Wiltshire, M. Robinson, H. Lewis, M. Bates, K. Nichols and E. James (Eds), Landscape Evolution in the Middle Thames Valley Heathrow Terminal 5 Excavations Volume 1 (CD-ROM, 1). Oxford: Perry Oaks Framework Archaeology Monograph No. 1.
Garner, J. (2010a). Der Siegerländer Kuppelofen im europäischen Vergleich, Siegerland 87, 174–197.
Garner, J. (2010b). Der latènezeitliche Verhüttungsplatz in Siegen-Niederschelden „Wartestraße“, Metalla 17, 1–147.
Grimes, W.F. and Close-Brooks, J. (1993). The excavation of Caesar’s Camp. Heathrow, Harmondsworth, Middlesex, 1944, Proceedings of the Prehistoric Society 59, 303–360. doi: 10.1017/S0079497X00003832
Hardy, A. and Young, T.P. (2019). Iron Age smelting and medieval charcoal production at Fleet Hill Farm, Eversley Quarry, Finchampstead, Wokingham. Archaeological investigations in 2009-2011, Berkshire Archaeological Journal 84, 43–65.
Jensen, N.L. (1968). A treatise on iron ore as found in the bogs and swamps of Norway and the process of turning it into iron and steel, Abridged translation of Evenstad 1790, Bulletin of the Historical Metallurgy Group 2, 61–65.
Lewis, J., Crabb, S. and, Ford, S. (2013). Bronze Age urns, Iron Age iron smelting and Saxon charcoal production at Sadler’s End, Sindlesham, Wokingham, Berkshire. In S. Preston (Ed.) Iron Age production sites in Berkshire, Excavations 2003 – 2012 (pp. 1–34). Reading: Thames Valley Archaeological Services (Monograph 16).
Natural England (2010). England’s peatlands; carbon storage and greenhouse gases. York: Natural England (Natural England Report 257).
Paynter, S. (2002). Iron-working slag. In A. Holmes (Ed.), Clearwell Quarry Extension, Stowe Hill, Gloucestershire (pp. 6–7). Oxford: Oxford Archaeology (unpublished report).
Paynter, S. (2007). Innovations in bloomery smelting in Iron Age and Romano-British England. In S. La Niece, D. Hook and P. Craddock (Eds.), Metals and Mines. Studies in Archaeometallurgy (pp. 202–210). London: Archetype Publications in association with the British Museum.
Paynter, S., Crew P., Blakelock, E. and Hatton, G. (2015). Spinel-rich slag and slag inclusions from a bloomery smelting and smithing experiment with a sideritic ore, Historical Metallurgy 49, 126–143.
Sauder, L. (2013). An American bloomery in Sussex. In D. Dungworth and R.C.P. Doolan (Eds.), Accidental and experimental archaeometallurgy (pp. 69–74). London: Historical Metallurgy Society (HMS Occasional Publication No 7).
Seager Thomas, M. (2010). A re-contextualisation of the prehistoric pottery from the Surrey hillforts of Hascombe, Holmbury and Anstiebury, Surrey Archaeological Collections 95, 1–33.
Smart, C., Young, T., Allan, J., Dawson, D., Taylor, R.T., Andersen, J., Rollinson, G., Challinor, D., Jones, J., Marshall, P., Tompkins, M., Collings, T., Keen, O., Bronk Ramsey, C., Dunbar, E. and Reimar, P. (2018). Industry and the making of a rural landscape: iron and pottery production at Churchill’s Farm, Hemyock, Devon. Oxford: BAR Publishing (BAR British Series 636). doi: 10.30861/9781407316260
Stöllner, T. (2014). The Siegerland as an iron production area during the first millennium BC: a regional approach to a famous mining region. In B. Cech and Th. Rehren (Eds.), Early Iron in Europe (pp. 43–64). Montagnac: Instrumenten Europe (Monographies Instrumentum 50).
Wagner, D.B. (1990). Ancient carburisation of iron to steel: a comment, Archeomaterials 4, 111–117.
West Sussex Archaeology (2014a). Archaeological Assessment and Written Scheme of Investigation for Archaeological Works at Folly Court, Barkham Road, Wokingham, Berkshire. Petersfield: West Sussex Archaeology (unpublished report).
West Sussex Archaeology (2014b). Written Scheme of Investigation for Archaeological Works at Folly Court, Barkham Road, Wokingham, Berkshire. Petersfield: West Sussex Archaeology (unpublished report).
West Sussex Archaeology (2018). Report on Archaeological Works at Folly Court, Barkham Road, Wokingham, Berkshire. Petersfield: West Sussex Archaeology (unpublished report).
Young, T.P. (2011). Some preliminary observations on hammerscale and its implications for understanding welding, Historical Metallurgy 45, 26–41.
Young, T.P. (2015a). Assessment of archaeometallurgical residues from Truro EDC. Caerphilly: GeoArch (Report 2015-13).
Young, T.P. (2015b). Assessment of archaeometallurgical residues from Yorkley, Gloucestershire. Caerphilly: GeoArch (Report 2015-24).
Young, T.P. (2016a). Archaeometallurgical residues from Tolgarrick Farm, Truro, Cornwall. Caerphilly: GeoArch (Report 2016-19).
Young, T.P. (2016b). Archaeometallurgical residues from Fleet Hill Farm, Finchampstead, Berkshire. Caerphilly: GeoArch (Report 2016/35).
Young, T.P. (2016c). Ironworking residues from Tregurra, Truro, Cornwall. Caerphilly: GeoArch (Report 2016/38).
Young, T.P. (2018a). Archaeometallurgical residues from Folly Court, Wokingham, Berkshire. Caerphilly: GeoArch (Report 2018/15).
Young, T.P. (2018b). Assessment of archaeometallurgical residues from Lockleaze (Ding Crusaders). Caerphilly: GeoArch (Report 2018/24).
Young, T.P. (2020). Archaeometallurgical residues from Hartshill Copse (HCB01). Caerphilly: GeoArch (Report 2020/17).
Young, T.P. (2022a). Archaeometallurgical residues from Bexhill. Caerphilly: GeoArch (Report 2022/09).
Young, T.P. (2022b). Chapter 7. Archaeometallurgy. In S.R. Taylor (Ed.), Down the bright stream: the prehistory of Woodcock Corner and the Tregurra Valley, Cornwall (pp. 170–204). Oxford: Archaeopress. doi: 10.2307/j.ctv2nwq8zn.15
Young, T.P. and Hart, R. (2021). The refining process (2): new data from Ynysfach Ironworks, Merthyr Tydfil, Historical Metallurgy 51(1), 34–50.
How to Cite
Iron Age iron smelting, Folly Court, Wokingham and the interpretation of ’dome’ furnaces. (2025). Historical Metallurgy, 55(1), 30-46. https://doi.org/10.54841/hm.671
Issue
Section
Articles
How to Cite
Iron Age iron smelting, Folly Court, Wokingham and the interpretation of ’dome’ furnaces. (2025). Historical Metallurgy, 55(1), 30-46. https://doi.org/10.54841/hm.671