2006:1771 - Derroon, Sligo

NMI Burial Excavation Records

County: Sligo Site name: Derroon

Sites and Monuments Record No.: SL033–051 Licence number: 06E0720

Author: Margaret Keane, DoEHLG, Dún Scéine, Harcourt Lane, Dublin 2.

Site type: Iron Age ring-barrow

Period/Dating:

ITM: E 566408m, N 816995m

Latitude, Longitude (decimal degrees): 54.100939, -8.513591

This site was levelled in April 2006. Following this, a short excavation was conducted for three weeks on 1–18 August 2006, funded by the rescue budget of the National Monuments Service, Department of Environment, Heritage and Local Government. The ring-barrow is one of a series of barrows within a linear barrow cemetery running from the south at Carrigans Upper townland, through Derroon townland to Rathdooney Beg townland at the north. There is a small companion monument, a bowl barrow, situated within the same field just 50m to the west. Prior to its reduction, the monument had been a well-defined example of its class, with a circular flat-topped mound, internal fosse and pronounced external bank, c. 27m in overall diameter. The monument was one of a number of barrows which had been surveyed and profiled during fieldwork in the Barony of Corran in the early 1990s by Jean Farrelly and the author.
The aim of the work was to establish and record the levels of damage to the monument, to excavate any truncated deposits and to retrieve exposed artefacts and dating evidence. As the original profile is available, as recorded in 1992, it is hoped to reconstruct the monument using the excavated deposits and introduced topsoil.
Prior to excavation, the levelled remains had a mounded appearance following the contours of the natural topography. The bank had been demolished. The well-defined ditch had been infilled and several machine-cut pits had been cut and backfilled into the top of the mound.
During the initial cleaning back of the monument surface significant quantities of cremated bone, copper alloy, flint and chert and a single glass bead were recovered. All excavated material was sieved. Several artefacts were recovered during sieving, including beads/toggles, pieces of copper alloy and metal pins, burnt bone, flint and chert artefacts, etc., despite the previous hand excavation of all features.
It was decided to concentrate excavation works on the western side of the crest of the mound, where charcoal-rich deposits were identified. In addition to this, a single trench was excavated from the outer edge of the central mound through the internal ditch and across the bank in order to record the ditch profile and to examine its infilling.
The excavated ditch was originally (prior to levelling) c. 2.5m wide at the top with a depth of c. 0.9m. It was cut sharply on the external edge to a rounded base, with a shallower profile on the internal mound side. There were a number of simple fills in the ditch surmounted by introduced material from the levelling. The mound sloped upwards from the ditch and some constructional layers of the mound make-up were revealed during excavation. A single post-hole was recorded just inside the edge of the mound crest. Aside from the machine damage, a series of deposits and pits representing a range of activities were recorded across the mound crest. The upper deposits were spreads of black charcoal-rich soils with burnt bone and occasional artefacts interleaving with a spread of compact white/grey silt. The latter may have been introduced to seal underlying deposits or to create a level upper surface. Some confined burning in situ was observed and the burnt material spread across the site may represent rakings of the pyre material. The removal of the upper horizons revealed a series of pits across the mound. A total of eight individual pits clustering towards the centre of the mound were recorded. They ranged in width from 1.3m for the largest to just 0.3m wide for the smallest. Most were filled with significant deposits of burnt bone, in a clayey matrix with occasional artefacts. They varied in complexity and depth. The most impressive was c. 0.5m in depth with a basal deposit of cremated bone and upper fills rich in charcoal and burnt bone. The interior edges of some of the pits were significantly charred. Excavation ceased with the removal of pit fills and truncated upper horizons on the crest of the mound.
The artefactual remains recovered include ten glass beads or bead fragments of a range of form and colour, two unperforated glass beads/toggles, a single copper alloy spiral ring, five copper alloy pins, a copper alloy rod, small amounts of unidentifiable iron fragments, some pieces of slag, worked flint and chert, fragments of copper alloy and two small pieces of modern glass. Some artefacts were burnt, some unburnt. One of the glass beads is exquisite; it is made of clear glass with a yellow spiral inlay, similar to beads from Meare, near Glastonbury in Britain. The deposition of finds, some in secure contexts with significant quantities of cremated bone, should allow for useful dating of deposits and associated artefacts. No ceramic remains were recovered and it is anticipated that the excavated remains date to the Iron Age.