Rubha Port an t-Seilich is a rocky promontory which protrudes between the bays of Port Mòr in the north and Fionn-phort in the south on the west coast of the Sound of Islay. The stone artefacts had been collected from a terrace forming a flat area approximately 40m by 30m, its boundary being formed by a steep slope to the east (leading to the seashore), a sallow thicket and small burn to the north, a small (3m) vertical cliff to the west, and a protruding rock outcrop and slope towards boggy ground to the south. Traces of recent activity in the form of rig and furrow cultivation, walls and ditches are located on and immediately surrounding the terrace; the extent of vegetation cover precluded a survey of these standing remains during the archaeological evaluation.
To explore the terrace, twenty 1m2 test-pits were excavated on a five metre grid, covering its entire extent; the size of the test pits reflected the depth and nature of the deposits, several requiring large angular stone blocks (collapse from the cliff) to be removed. The test-pits were designated by grid co-ordinates, 0/0 in the south-west corner to 15/20 in the north-east. Each was fully excavated to the underlying bedrock, this being found at a depth of 10-20cm immediately below the top soil on the eastern edge of the terrace but over a metre deep at the western edge, below the low cliff and where colluvium had accumulated. These test-pits and those within the central part of the terrace contained stratified deposits. Artefacts were hand collected during excavation and by sorting wet sieve residues: 30 litre samples from each test-pit were washed through a 3mm mesh, while further samples were taken from selected contexts that appeared of particular archaeological importance.
The stratigraphic sequences within each test-pit were given their own unique set of context numbers. A provisional correlation between test-pit contexts was made to derive an overall sequence of deposits, these being given generic unit numbers within this report (RPS1, RPS2 and so on). Deposits of varying coloured sands (2-10cm thick, yellow to grey, RPS1) were found immediately above the bedrock. These were culturally sterile and most likely derived from degraded bedrock. Overlying these were mottled sandysilts (RPS214) that filled bedrock crevices within some of the test-pits and contained low densities of stone artefacts. Features had been cut into this horizon: post-holes were found in two of the test-pits (15/5 and 15/10) and traces of a wall within test-pit 10/15. The bed rock exposed at the base of the posthole in test-pit 15/5 was noticeably cracked and reddened, suggesting intense heat. Following the activity designated by these features, a horizon of black peaty silt containing a high percentage of gravel (RPS3) formed across the site, either sealing these features or forming directly above the mottled sands (RPS2). This horizon and all later horizons contained high densities of chipped stone artefacts and coarse stone artefacts.
Two of the test-pits (5/0) and (10/15) had a thin band of clean peat (lacking gravel) on either side of this horizon, while several test-pits (5/0, 5/10, 10/15, 5/15 and 15/10) had a distinct 'shingle' horizon (RPS4) either between or underlying the peaty-horizons (RPS3). The peaty and shingle horizons in test-pits 0,10, 5,10 and 10,15 contained small fragments of animal bone. These peaty and shingle horizons were sealed by poorlysorted colluvium (RPS5) in the test-pits at the western side of the terrace close to the small cliff; immediately above this, and above the black peaty silts (RPS3) in the test-pits to the eastern side of the terrace, there was a loamy subsoil (RPS6) containing fragments of glazed pottery. This had a uniform character across the site suggestive of a cultivated soil, most likely relating to the surrounding walls, ditches and rig & furrow and was immediately below a top-soil/ bracken root mass (RPS7).
The stone artefacts
Approximately 9500 chipped stone artefacts were recovered from Rubha Port an t-Seilich. As at Storakaig, this is a notably high total for such small scale fieldwork suggesting intensive Mesolithic activity. The artefacts from Rubha Port an t-Seilich derived from all contexts above the degraded bedrock and were notably dense within the topsoil (RPS6), subsoil (RPS5) and colluvium (RPS4). Limited resources meant that only a small sample (400) of these artefacts could be catalogued, these being primarily selected from the sandy (RPS2), peaty (RPS3) and shingle (RPS5) horizons. All horizons contained diagnostic Mesolithic artefacts in the form of either microliths, bladelets, blade cores and/or core trimming elements. A few artefacts of a potential Neolithic date were identified within the assemblage coming from the shingle layer (RPS4), which accords with similar artefacts found within the initial surface collection of 2009. Other than these few artefacts, the artefact collection as a whole represents a 'classic' Mesolithic narrow blade assemblage. There is a wide range of tool types - microliths (of various types), scrapers, notches, denticulates and so forth, suggesting a diverse range of past activities.
Flint and quartz had been used as the raw materials, with the highest percentage of quartz artefacts (13%) coming from the mottled sand horizon (RPS2). The majority of artefacts are in good condition, with only 2% having battered edges and 3% rolled edges. Nearly 20% of the assemblage is burnt. The flint artefacts had been made from small beach pebbles, but few had any cortex present. This suggests that the initial stages of artefact manufacture had been undertaken elsewhere, either in the immediate vicinity of the site or at some distance - the primary source of flint pebbles on Islay being on the west coast. In light of the platform core technology represented (46), the intention has evidently been to produce small, fine blades, a selection of which was then retouched to form tools such as microliths (47), awls and burins. Larger tools, such as scrapers and notches had been made from flakes. There are considerable differences in the artefact collections coming from the different horizons at the site. That from the basal sandy layers represents higher levels of tool making activity, a higher frequency of blades rather than flakes, and a greater use of quartz than the collection from the overlying peat and colluviums layers. The artefacts from within the peat and shingle layers are more frequently burnt. There is also considerable variability in the artefact collections coming from the same horizon but different test-pits: the peat horizons in test-pits 10/5 and 0/5 had notable differences in the frequencies of burnt artefacts, regular bladelets and proportion of quartz. Overall, the artefact collections suggest there had been changes in the activities taking place at Rubha Port an t-Seilich over the period of occupation, while there had also been different activities taking place in different areas of the site at any one time.
Approximately 200 coarse stone artefacts were recovered from Rubha Port an t-Seilich - a particularly large and impressive collection for the Mesolithic of western Scotland. This collection was more diverse than that from Storakaig, including some particular fine, flat elongated artefacts, and rounded, surface-pecked beach cobbles.
The animal bones
Seventeen fragments of animal bone were recovered from Rubha Port an t-Seilich, these coming from the sand (RPS2) and peat (RPS3) horizons. Their condition was strikingly similar to the bone fragments from Storakaig: the majority being less than 10mm in size, heavily burnt but otherwise in good condition. Only five fragments were identifiable: roe deer is represented by a sesamoid, red deer by a scaphoid carpal, and wild boar by a patella. Two fish caudal vertebrae probably come from sea bass (Dicentrarchus labrax). As at Storakaig, the highly calcined nature of the bone fragments suggests that they had originally been placed within a fire, either as a source of fuel or simply when discarded.
The plant remains
Approximately 270 pieces of wood charcoal were collected from thirteen of the twenty test-pits at Rubha Port an t-Seilich15. These were collected on-site either by hand-picking or sieving using a 3mm mesh. The distribution of wood charcoal is restricted to the test-pits located within the centre of the terrace, with peripheral test-pits largely devoid of charred plant remains. Approximately 90% of the wood charcoal assemblage is well-preserved, consisting of fragments larger than 4mm. As such, it has considerable potential for reconstructing local woodland growing within the vicinity of the site. Approximately 160 fragments of charred hazelnut shell were also collected with a similar distribution across the site to that of the wood charcoal. Whether the Rubha Port an t-Seilich wood charcoal assemblage changes in species diversity and frequency over time remains to be determined, as does the relationship between the site stratigraphy and the occurrence of preserved plant remains. This will require a further systematic programme of bulk sampling and sieving of specific contexts.