EMAP_2012_Report_6_1.pdf (7.3 MB) - The Heritage Council

2012 gazetteer as well as at Randalstown (Wood-Martin 1886);and Nendrum (Lawlor 1925,
143; Bourke 2007, 407), (Appendix 1). Iron hammer heads have been found on at least three
sites in the EMAP 2012 gazetteer as well as at Killyvilla (D'Arcy 1897a, 220) and Scandinavian
Dublin (McGrail 1993, 167). Comber (2008, 118) has suggested that hammer-stones and
wooden mallets may have fulfilled similar iron-working functions and the former are known
from at least fifteen sites (Appendix 1). In contrast, wooden mallets only survive in wetland
contexts at Lagore (Hencken 1950, 163); Ballinderry I (Hencken 1936, 172) and Ballinderry II
(Hencken 1942, 60).
Other tools used in the final forging process included iron chisels and punches. Iron chisels
are known from at least 25 sites in the EMAP 2012 gazetteer as well as Craigywarren (Coffey
1906, 115); Moylarg (Buick 1893, 32) and Moyne (Manning 1987, 54), (Appendix 1). Files,
whetstones and grindstones were used for sharpening, shaping and smoothing iron and
metal tools, blades, points and other objects. Association with metalworking sites can be seen
at Lowpark with rotary grindstones and a hone sharpening stone (Higgins 2010, 2). Iron files
are difficult to identify due to the poor preservation of iron but possible examples are known
from Scandinavian Waterford (Scully 1997b, 469) and Woodstown (O'Brien et al. 2005, 70).
2.3: Archaeological evidence for early medieval iron manufacturing
Archaeological evidence for the production of iron comes from a range of sources. Heavily
scorched pits representing the remains of furnaces or hearths are frequently found. The
archaeological residues of the iron working process come in the form of slags, metallurgical
ceramics, fuel waste, vitrified fuel ash and ore (Photos-Jones 2011, clxi). These can be found
within a variety of features on settlement sites such as ditches and pits or more directly as
dumps of industrial waste or within heavily scorched features associated with iron production
representing different kinds of hearths and furnaces. Direct evidence for iron-working at
some stage in the process comes from a total of 199/317 settlement sites (Map 2.1;
Appendix 1). Previous syntheses noted 49 sites with evidence for iron-working which included
five ecclesiastical sites not considered in the EMAP sample (Comber 2008, 181). At many
earlier sites iron slag and other metallurgical residues were described but was difficult to
quantify. Comber originally classified evidence for iron-working as average, minimal or
extensive. Metallurgical residues and features can be found in association with structural
remains, storage and refuse pits and ancillary working areas. Investigative techniques to
better understand these processes on site include consultation with specialist, extensive
sampling of metallurgical residue, magnetic and/or phosphate survey of soils. The latter can
include the systematic use of a magnet around hearths, pits and other features. Laboratory
processes include analysis of metallurgical residues, studies of fuel sources and scientific
analysis of selected artefacts. Experimental work is also very important in trying to
understand the archaeological evidence with a number of important recent studies of early
medieval Irish iron technology (Stevens 2010,
http://www.geoarch.co.uk/experimental/bell.html,
http://www.seandalaiocht.com/1/post/2010/11/smelt-2010-full-video-in-hd.html)
2.3.1: Raw materials
The principal source of iron in early medieval Ireland is believed to be bog iron ore (Wallace
and Anguilano 2010b, 70); a deposit formed under wet conditions when iron-bearing surface
waters meet organic material (Tylecote 1986, 125). Bog iron ore and bog iron slag have
been found at the rath complex of Cush (Ó Ríordáin 1940, 154), the rath at Mullaghbane
(Spence 1972, 43) and at Reask (Fanning 1981). Bog ore has been found at St Gobnet’s,
Ballyvourney, Lough Faughan (Scott 1991, 151) and Clonfad (Stevens 2007, 42). The
importance of specialist analysis of such samples and their context is demonstrated by the
Clonfad sample which may have resulted from secondary mineralisation of
archaeometallurgical residue on the side of a stream (Young 2009a, 25). Therefore there are
many factors to take into account when considering ore samples. Photos-Jones (2008a, 186)
concluded that the high manganese content in iron ore fragments found on excavated sites
on the border of Counties Kildare and Meath, for example at Killickaweeney and Johnstown,
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