Archaeological signatures of landscape and settlement change on the Isle of Harris

Between 2004 and 2011, a programme of archaeological investigation by the University of Birmingham on the Isle of Harris, a distinctive island forming part of the Western Isles of Scotland, has allowed the archaeological remains of this enigmatic place to be further characterised and understood. Despite intensive archaeological interest in the archipelago for a number of decades, the Isle of Harris has been overlooked and only now are we beginning to identify the archaeological resource and make comparisons to the wealth of published data from islands such as the Uists, Barra and Lewis. This paper highlights some generic overall patterns of archaeological signatures on the Isle which has been identified through a range of archaeological methods including field walking, intrusive excavation, aerial reconnaissance, geophysical and topographical survey, and documentary research. Several key case studies will be introduced including upland shieling complexes and mulitperiod settlement sites on the west coast machair systems. The purpose of the paper is not to present a gazetteer of the results of the work to date, but to highlight some of the key findings with a view to demonstrating that the Isle of Harris is directly comparable with the archaeologically rich landscapes of the other islands

⁸⁷Sr/⁸⁶Sr: A new discriminant for provenancing neolithic porcellanite artifacts from Ireland

Antrim porcellanite (thermally metamorphosed Tertiary laterite) was the most common raw material used in the production of stone implements during the Neolithic in Ireland and was worked at two localities in North Antrim: Tievebulliagh, near Cushendall and Brockley on Rathlin Island. Attempts have been made to provenance material from these two known sources, the most successful to date being the use of geochemical data (Sr and Yppm). Here we present a new geochemical discriminant-Sr isotopic data-which reveal that Tievebulliagh and Brockley porcellanites are distinctive. Present-day 87Sr/86Sr ratios form two discrete groupings ranging from 0.705894±25-0.706443±24 at Tievebulliagh and 0.704088±27-0.704587±25 at Brockley. A coherent relationship between 87Sr/86Sr and Sr (ppm) reiterates the use of Sr content as a discriminant and illustrates the geochemical variability of Sr between these two sources. Although this is a destructive technique, 87Sr/86Sr represents the best discriminant to date for Antrim porcellanites and will enable definitive provenancing of porcellanite artifacts from Ireland with important archaeological implications