EMAP_2012_Report_6_1.pdf (7.3 MB) - The Heritage Council

metal-working like Castlefarm (O’Connell & Clark 2009, 14) and Deer Park Farms (Bayley
2011, 346-251). Bar-shaped ingots are the most common form and typically measure
between 5 and 10cm and 1cm in thickness (Comber 2008, 135). These could have been used
as convenient forms for storage or trade or could either have been hammered out on an anvil
to form sheets of metal or melted down in crucibles for pouring into clay moulds, from which
various objects could be cast.
3.2.1: Crucibles
Crucibles are commonly found on early medieval settlements but were importantly specific to
non-ferrous metal-working. A total of 55 settlements of the 62 sites with evidence for nonferrous
metal-working within the EMAP 2012 gazetteer had evidence for crucibles and in 37
cases this was the only evidence for this type of craft (Fig. 3.1; Appendix 1.2). Comber’s
analysis of ringfort and contemporary settlements identified 21 settlement sites with crucibles
along with a further eight ecclesiastical sites. Estimating the number of crucibles per site is
difficult as they are often given in publications as sherds or fragments rather than a minimum
number of individual vessels. Therefore the numbers represented by fragments depends on
the degree of fragmentation. This is in addition to those found at ecclesiastical sites such as
Reask, Movilla Abbey, Clonmacnoise along with multiple locations in Armagh (Comber 2008).
Crucibles from Armagh and Moynagh Lough bear the mark of tongs used to handle them.
Many of these may have been represented by small numbers of sherds. The sites with no
evidence for ferrous metal-working which contained crucibles had no excavated furnaces
suggesting they could have been used in conjunction with domestic hearths.
Figure 3.1: Crucibles found on different types of early medieval settlement (N=64)
Most crucibles were made of clay though stone examples are also known. Several different
types have been identified (Laing 2006, 115-7): the most common type were small with
triangular mouths (pyramidal type) though deeper, bag-shaped and shallow, round-bottomed
and flat-bottomed crucibles are also known (Edwards 1990, 90). Some details are available
on the manufacture of these objects. A total of 26 sherds were found at Clonfad, all
pyramidal in form (Young 2009a, 8.1). They were made from clay with an organic temper,
possibly hair.
Many crucibles have an internal glassy glaze was created when the hot contents combined
with silicates and alumina in the wall of the vessel cool rapidly (Wallace 2009, 9). Relatively
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