VSF 2010 Report - Nabo

slag was identified as flowed. The undiagnostic flowed slag fragments are likely to derive
from production slags. The slag recovered from this context corresponds to find 119.
ID. [318]
Mag.
Max. Dimensions (cm)
Min. Dimensions (cm)
L W D L W D
Count
Weight (g)
Undiagnostic * 4 3.5 2.5 >0.5 >0.5 >0.5 501 1351.0
Flowed 6 4.5 3 >0.5 >0.5 >0.5 122 919.3
Tap
Smelting 6 5.5 3.5 2.5 1.5 1 15 343.7
SHB
Hammerscale x - 2.5
Fuel ash 3 2.5 1 1 12.9
Technical vitrif. 2.5 2 0.5 1 2.5
Ferr. conc. * 6 5 2.5 1 1 1 22 337.0
Charcoal - 0.6
Other - 2.1
Total 662 2971.4
Pit [329] (Fill contexts [319] and [324])
Pit [329] contained a large deposit of iron slag. It is important to note that this pit cut into the
collapse of Structure 3, overlying the turf wall in the northeast corner (Milek 2005: 57). A
large deposit of slag was recovered from pit [329]. Due to the grading of the deposit and
diffuse boundary between its upper and lower parts, the fill was arbitrarily divided into
contexts [319] and [324]. Towards the lower limits of the feature, the ratio of charcoal to slag
increased (see Fig. 19, Milek 2005: 57).
Pit [329] contains a substantially large deposit of slag when compared to the rest of
the site, totaling over 60kg. Nearly a third of the slag recovered was identified as iron
production slag. A small proportion of the iron production residues could be distinguished as
tap slag. Pit [329] also contained the highest concentration of technical vitrifications that are
thought to originate from furnace construction(s). It is, therefore, not surprising to also
observe that the pit contains the most ferruginous concretions compared to the other contexts,
much of which is thought to represent iron ore residues. A significant amount of the
undiagnostic residues is comprised of flowed slag, which appears to be fragmentary
production slags due to the frequency of charcoal impressions observed. The assemblage
contained fragments of smithing hearth bottoms which may derive from bloom refining in
association with the smelting taking place. The slag recovered from context [319]
corresponds to finds 113, and the slag from [324] corresponds with find 112.
ID. [319]
Mag.
Max. Dimensions (cm)
Min. Dimensions (cm)
L W D L W D
Count
Weight (g)
Undiagnostic * 9 7 6 >0.5 >0.5 >0.5 1009 14170.5
Flowed * 8 5.5 3.5 1.5 1 0.5 576 8145.1
Tap * 11.5 8.5 5.5 2 1.5 1 27 1822.5
Smelting * 11.5 6 4.5 1.5 1 1 390 13150.0
SHB x 10 7.5 3.5 3 3 2 13 1037.5
Hammerscale x - 38.6
Fuel ash 3 2.5 1.5 1 1 1 24 149.4
Technical vitrif. * 11 9.5 4.5 2 1 1 32 1668.2
Ferr. conc. x 6.5 4 4 >0.5 >0.5 >0.5 147 1327.4
Charcoal
Other - 472.0
Total 2218 41981.2
142