Case Study 8: Balure Dun Excavation

Balure Dun Excavation

Roddy Regan, Kilmartin Museum

 

Figure 93: General view of Dun Location ©Kilmartin Museum

Introduction

The dun site at Balure (NMRS No. NR78NE 36) (Figure 93) was unknown until quite recently when it was noted as an enclosure and/or cairn within the Forestry Commission's heritage database for North Knapdale Forest. The site was briefly surveyed in 2004 as part of an archaeological survey of North Knapdale Forest undertaken by Kilmartin Museum, which confirmed its status as a likely dun structure (Regan 2005). Further survey and archaeological evaluation work was undertaken in 2006 as part of the Dalriada Project that enhanced the picture of the dun as consisting of a sub-circular inner enclosure with a series of outworks to the N and S (Regan and Webb 2006). Two phases of excavation, totalling six weeks were undertaken in October 2008 and May 2009. The preliminary results of these excavation phases appeared in the subsequent Data Structure Reports which can be accessed on the Kilmartin Museum website [http://www.kilmartin.org/] (Regan 2008, Regan 2009a).

Site Location

The dun occupies the S end of a steep sided SW/NE oriented natural knoll occupying a commanding position above the sloping glens to the E and W situated about 500m S of the deserted settlement of Balure and 300m W of Loch Laraiche (Centred NGR NR 78270 85750, 142m AOD) (Figure 94).

Figure 94: Plan of dun showing layout and excavated area © Kilmartin Museum

The Dun Structure (Figure 95)

The upper enclosed area (Enclosure 1) can perhaps be interpreted as the main enclosed area and had a maximum width of 11.70m between the S and N walls and 8m between the E wall and the steep natural rock outcrop forming its W side. The outworks effectively divide the ridge into a series of outer enclosures (Enclosures 2-4). The entrance to the dun lay on the S side where two entrance gaps were identified, accessing Enclosures 1 and 2. It is still possible an entrance lay to the N but none was positively identified during the excavation work. The uneven and more rugged ground within Enclosure 3 possibly precludes the presence of any substantial structure within the enclosed area and this might similarly be the case within Enclosure 4, although there is enough level ground within either that could have contained smaller structures. All the enclosure walls were constructed in drystone rubble, mainly blocks of chlorite schist (epidiorite) the stone likely locally sourced given that there is evidence of quarrying into the natural rock out-crops (see below). The walls appear to have been extensively robbed and stood no higher than 0.90m.

The footings of the wall on the E side were relatively wide (c.5m) which might indicate that the wall was originally battered on this side. Within the wall mass, particularly on the S side there could be discerned 'rows' of larger elongated stones that give the appearance of 'median faces'. These 'rows' appear to be integral to the primary construction of the wall rather than representing consecutive building phases and, as has been noted before, may have functioned to counteract internal slumping of the wall mass (Harding 2004a, Henderson and Gilmour 2011). The same building technique appeared to have been used within the wider foundation on the E side where larger stones appear to have been used to retain or consolidate smaller stones or rubble within foundation 'blocks', a construction technique Harding refers to as 'quasi-casement'.

The walls of the outworks appeared to be less substantial, although these again had been extensively robbed and disturbed, with only the footings surviving. The construction sequence of the walls suggested that Enclosure 1 was built prior to Enclosure 2. The presence of dumped or midden material lying under the wall of Enclosure 2 also indicates earlier occupation on the ridge most likely centred on Enclosure 1. The relationship however between Enclosures 3 and 4 vis a vis Enclosures 1 and 2 is less clear. Enclosure 2 was less extensively excavated but the presence of post settings suggest this was partly roofed, or contained other structures.

The foundation walls of the dun appear to the eye to be crudely built, especially when compared to the walling of other duns in the area, for example Castle Dounie (RCAHMS 1988, No.285), Druim an Duin (RCAHMS 1988, No.293) and Dun Rostan (RCAHMS 1988, No.315), which appear to use more sophisticated coursing within their walls. This however may be more of a reflection of the availability and type of local stone used in the construction of the dun rather than an indication of status or technical ability, the above duns using more regular blocks than those generally used at Balure. Regular blocks where they are used, provided the main facing blocks within the walls and within the 'medial faces' seen within the wall construction, these perhaps used as stabilisation between the more rounded stones that comprise the bulk of the walls. It would be informative to compare the materials used within the construction of other Mid Argyll duns where 'median face' have been noted, such as at Dun a' Bhuilg (RCAHMS 1988, No.246), Ballymeanoch (RCAHMS 1988, No.273), Barr Iola (RCAHMS 1988, No.277), Cnoc a' Chaisteal (RCAHMS 1988, No.286) and Loch Glashan (RCAHMS 1988, No.322; Henderson and Gilmour 2011).

Figure 95: Detail of Dun Structure  © Kilmartin Museum

In terms of size the dun structure is within the middle range of dun enclosures, although its outworks increase its overall internal dimensions. While not complicated in layout, the outwork walls effectively control the access to the summit along the less steep slopes of the ridge. At present only Enclosures 1 and 2 would appear level enough to contain any structures, although this does not preclude areas of 'outside' activity having occurred within the outer works of Enclosures 3 and 4. The outworks might suggest a relatively sophisticated approach to the defensive construction if constructed from the beginning although it is likely they developed in a more piecemeal fashion. Other duns in Mid Argyll with similar outworks have been noted, including; Dun na Caistail A' Chrannag (RCAHMS 1988, No.266), Dun Rostan (RCAHMS 1988, No.315), Dun Cragach (RCAHMS 1988, No.304) and Dun Bhronaig (RCAHMS 1988, No.302). As the outer enclosure walls at Balure were not very apparent before excavation it would not be surprising if more similar out-works came to light through more intensive survey and/or excavation work, especially around the more denuded dun sites. The presence of internal posts indicated that Enclosure 1 was partially roofed, if not wholly so, while post placements within Enclosure 2 also indicate the possibility of a roofed structure.

The two C14 dates indicate that Balure dun was occupied between the 2nd century BC and the 1st century AD (SUERC-31664 (GU-22596) and SUERC-31665 (GU-22597), 200 BC - 80 AD 95.4% probability).

Within Enclosure 1 (Figure 96) the hearth sequence along with a rotary quern fragment, processed grain, pottery and a quantity of stone 'tools' suggest the dun structure was utilised as a 'domestic place'.

Figure 96: Enclosure 1 with hearth in centre forground © Kilmartin Museum

Other fire installations along the E wall of the Enclosure and the evidence of burning on its NW side along with the presence of wood charcoal, iron slag, crucible fragments and a possible mould suggests iron and other metal working also took place in this area. The recovery of similar metal working waste including hammerscale from Enclosure 2 also indicates this enclosure was also used for metal working. Adjacent to where the main concentration of hammerscale was located was a large flat natural outcrop and it is attractive to view this as being utilised as an anvil stone.

Small quantities of carbonised barley and oats were recovered from the collected samples along with wood charcoal including hazel, oak and birch. Bone preservation within the acidic soils was extremely poor, although burnt bone does survive. Unfortunately these were all small and not identifiable to taxa.

The range of finds from Balure is perhaps 'typical' of Argyll duns including three glass beads, an iron tool, some pottery and a range of metalworking debris. Reflecting other dun sites the bulk of the recovered artefacts were stone tools or stones modified with use, including a modified quernstone, other tools being polishers, rub-stones, hammer-stones, grinders and possible palettes. Several worked objects of oil schist slate were also recovered, two of these circular/rounded in shape with one having a centrally pierced hole, suggesting their use as spindle whorls or disc whorls similar to those found at Barnluasgan (Regan and Webb 2006, 2007). A third piece also had a centrally pierced hole suggesting it broke in production with others being possible rough-outs or production waste. The pottery assemblage while limited in terms of vessels present indicates the use of small gobular pots with a fairly fine handmade fabric. This has few parallels elsewhere in late Iron Age assemblages from excavated Argyll sites and might indicate a local tradition. Similar pottery, although again limited in number, was recovered from what may be a roundhouse site excavated at Carnassarie (Ellis 2008). The glass toggle beads are significant as they appear to be an indigenous phenomenon and generally found throughout the Atlantic region including Ireland, the Isle of Man and Scotland. In Argyll toggle beads have been recovered from Dun Fhinn (CANMORE ID 38467), Ronachan Bay (CANMORE ID 38964), Dunagoil (CANMORE ID 40291) and recently from Kilninian, Mull (CANMORE ID 294742), the later site indicating that the bead was in the process of being manufactured sometime between 200 BC - 100 AD (Bigwood 1964, Peltenburg 1979, Harding 2004b, Ellis pers. comm.). The bead from Balure along with those from Kilninian and Dun Fhinn were subject to analysis using Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) whereby chemical trace elements were identified suggesting the original provenance of the glass was the Mediterranean region and reused to produced locally manufactured beads (Bertini and Ellis pers. comm.). With the exception of the beads, all the material is likely to be of local origin and manufacture. The picture that emerges is of a self-sufficient agricultural community. As far as chronology is concerned, all of the material fits comfortably into a middle Iron Age tradition (c. 200BC- AD400), and there is no indication of early historic occupation.

Balure Dun Excavation Bibliography

  • Bigwood, W F L 1964 'Dun at Glenramskill, Campbeltown', Discovery and Excavation in Scotland, 1964, 18-19.
  • Ellis, C 2008 Carnassarie Excavation, Dalriada Project, Data Structure Report, Kilmartin Museum.
  • Harding, D W 2004a The Iron Age in Northern Britain: Celts and Romans, Natives and Invaders. Routledge: Abingdon.
  • Harding, D W 2004b 'Dunagoil, Bute, re-instated', Transactions of the Buteshire Natural History Society, 26, 1-19.
  • Regan, R 2005 North Knapdale Forest, Forestry Commission Archaeological Survey, Kilmartin Museum Report No. 4.
  • Regan, R 2006 Dalriada Project, Archaeological Evaluation, Data Structure Report, Kilmartin Museum Report No. 11.
  • Regan, R 2008 Balure Dun, Dalriada Project, Excavation Data Structure Report, Kilmartin Museum Report No.20.
  • Regan, R 2009 Balure Dun, Dalriada Project, Excavation Data Structure Report II, Kilmartin Museum Report.
  • Regan, R and S Webb 2006 Barnluasgan Dun and Enclosure, Dalriata Dun, Community Archaeology Project, Data Structure Report, Kilmartin Museum. Report No.10.
  • Regan, R and S Webb 2007 Barnluasgan Dun and Enclosure, Dalriata Dun, Community Archaeology Project, Data Structure Report, Kilmartin Museum. Report No. 12.
  • RCAHMS 1988 The Royal Commission on the Ancient and Historical Monuments of Scotland. Argyll: an Inventory of the Monuments: Vol. 6: Mid-Argyll and Cowal, Prehistoric and Early Historic Monuments. Edinburgh.
  • Peltenburg, E 1979 'Ronachan', Discovery and Excavation in Scotland, 30 - 31.