EMAP_2012_Report_6_1.pdf (7.3 MB) - The Heritage Council

93). One decorated millefiori rod at Garranes was found in situ inside a copper-alloy tube
which securely held the glass while slices were cut off (Ó Ríordáin 1942, 120).
In one of the very few studies on the subject, Henderson (1988a, 1988b) has investigated
the technological and scientific aspect of glass-working and its organisation in early medieval
Ireland in the context of his discussion of the evidence from Dunmisk. On the basis of glass
residues on crucible at Dunmisk, he (1988b, 120-23) established that glass was not only
worked but also manufactured from its constituent components at this early medieval Irish
site. He noted that the crucible residues were composed of raw materials, particularly silica
and tin oxide, which were used in glass-making. Bronze- and glass-working were found in the
same part of the site (Ivens 1989, 57), and it is likely that similar crucible types were used for
both. Further analysis of crucible residues from other sites is needed to provide more
information on the manufacturing process. Recent scientific analysis of red enamel from
Ireland and Britain suggests that it was made using re-used metallurgical slag or copper
making waste reheated in a crucible rather than as a result of the glass making process. The
blocks of enamel found from Kilmessan and Tara are now thought to be of earlier origin and
the results of a different technical process (Stapleton, Freestone and Bowman 1999, 913-
921).
4.4: Contexts of glass-working
Although evidence for glass-making is limited (Henderson 1988b), evidence for glass-working
has been found on a growing number of ecclesiastical sites including Movilla Abbey
(Henderson 1984, 98-9); Dunmisk (Ivens 1989, 57), and Cathedral Hill (Harden 1984, 135)
and Scotch Street (Lynn and McDowell 1988b, 60-1), both in Armagh. Most of the evidence
comprised glass rods, globules, scrap and occasionally crucibles. Comber (2008, 131) has
noted that where concentrations of glass-working evidence occur together, it was usually
undertaken in industrial quarters away from domestic structures. The craft was also spatially
and functionally associated with fine metalworking, using much of the same equipment, tools
and structural features. Glass-workers do not feature in any of the early Irish literary sources
which might suggest either a limited industry or more likely the manufacture of glass by
craft-workers of other disciplines, such as the fine metalworker (ibid. 131).
Both crafts have been found together at a number of sites. The glass and non-ferrous
metalworking at Dunmisk were concentrated in the northeast quadrant of the site but
ironworking was found primarily in the southwestern area. The furnaces used in
metalworking were probably employed in the working of vitreous materials and both crafts
have been found together just inside the southern quadrant of Garranes (Ó Ríordáin 1942,
86), in the eastern section at Lagore (Hencken 1950, 234) and the southern side of Cathedral
Hill, Armagh (Gaskell-Brown and Harper 1984, 111). Fine metalworking and enamelling were
undertaken together on the southern side of the Neolithic passage-tomb at Knowth and on
the west of the slope of the site (Eogan 1977, 74). The principal area consisted of a roughly
circular area of charcoal, c. 1.70m in diameter, against and spreading out from a small
rectangular stone set on edge (0.30m in length and 0.12m in height) that may have provided
some form of shelter for the fire. Finds consisted of two complete heating trays and a
fragment of another and parts of clay crucibles.
4.5: Levels of glass-working
Comber (2008, 131-2) has noted that this craftwork can be divided into three standard levels
of activity. A number of sites such as Seacash, Lissue and Rathbeg produced minimal
evidence for this craft, perhaps indicating the use and occasional repair of finished glass
artefacts such as beads and bangles. The most extensive evidence has been found at Lagore,
Moynagh Lough, Garryduff and Dunmisk. Garryduff and Lagore have produced the most
evidence with the latter site producing tools, beads, armlets, cullet, studs and their moulds,
millefiori remains and melted lumps and fragment of glass.
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