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University of Bradford eThesis This thesis is hosted in Bradford Scholars – The University of Bradford Open Access repository. Visit the repository for full metadata or to contact the repository team © University of Bradford. This work is licenced for reuse under a Creative Commons Licence. THE NEOLITHIC AND LATE IRON AGE POTTERY FROM POOL, SANDAY, ORKNEY An archaeological and technological consideration of coarse pottery manufacture at the Neolithic and Late Iron Age site of Pool, Orkney, incorporating X-Ray Fluorescence, Inductively Coupled Plasma Spectrometric and Petrological Analyses 2 Volumes Volume 1 Ann MACSWEEN submitted for the degree of Doctor of Philosophy Department of Archaeological Sciences University of Bradford 1990 ABSTRACT Ann MacSween The Neolithic and Late Iron Age Pottery from Pool, Sanday, Orkney: An archaeological and technological consideration of coarse pottery manufacture at the Iron Age site of Pool, Orkney, incorporating X-Ray Fluorescence, Inductively Coupled Plasma Spectrometric and Petrological Analyses Key Words: Neolithic; Iron Age; Orkney; pottery; X-ray Fluorescence; Inductively Coupled Plasma Spectrometry; Petrological Analysis The Neolithic and late Iron Age pottery from the settlement site of Pool, Sanday, Orkney, was studied on two levels. Firstly, a morphological and tech- nological study was carried out to establish a se- quence for the site. Secondly an assessment was made of the usefulness of X-ray Fluorescence Analysis, In- ductively Coupled Plasma Spectrometry and Petrological analysis to coarse ware studies, using the Pool assem- blage as a case study. Recording of technological and typological attributes allowed three phases of Neolithic pottery to be iden- tified. The earliest phase included sherds of Unstan Ware. This phase was followed by an assemblage char- acterised by pottery with incised decoration, which was stratified below a traditional Grooved Ware assem- blage. The change in pottery styles and manufacturing methods with the Grooved Ware indicated that it evolved elsewhere. Grass tempered and burnished pot- tery characterised the Iron Age assemblage. Pottery samples from all phases of the site were analysed by XRF and ICPS. In addition, pottery from late Iron Age sites in the area was analysed for com- parison with the Pool Iron Age pottery. XRF and ICPS analyses did not distinguish between either different phases at Pool or different Orcadian sites. This was attributed to the similarities in geological deposits over much of Orkney and the variations which can occur within a clay source. A clay survey was carried out in the vicinity of the site, and samples taken for comparison with the Pool pottery. Identification of rocks and minerals in thin section, and grain-size analysis, indicated that the Pool pottery was made locally to the site, and that both primary and secondary clays were used. It was concluded that petrological analysis is more suitable than elemental analysis in the study of coarse wares. CONTENTS ", List-of Tables i Preface iii SECTION A: GEOLOGICAL AND ARCHAEOLOGICAL BACKGROUND CHAPTER 1: GEOLOGICAL-BACKGROUND 1 1.1 The Geology of the Orkney Islands 1 1.1.1 Topography ý1 1.1.2 The Solid Geology 2 1.1.3 Drift Geology 4 1.2 The Geology of Sanday 5 CHAPTER 2: ARCHAEOLOGICAL BACKGROUND 8 2.1 Neolithic Background 8 2.1.1 Introduction 8 2.1.2 Funerary Monuments 8 2.1.3 Settlement-Sites 12 2.1.4 Scottish Neolithic Pottery 15 2.2 Background to the Early Historic Period 19 2.2.1 Scotland in the Early Historic Period 19 2.2.2 Historical and Placename Evidence 19 2.2.3 The Archaeology of the Pictish Heartland 22 2.2.4 'The Problem of the Picts' 25 2.2.5 The Archaeology of the 'Peripheral Picts' 27 2.2.6 The Late. Iron Age Pottery Sequence for the North 2.3 The Site of Poo1 rr 2.3.1 Introduction 2.3.2 Initial Recording and Survey 2.3.3 Excavation 2.3.4 The Neolithic Phases 2.3.5 The-'Abandonment' 2.3.6 The Iron Age Phases 2.3.7 Norse Occupation r CHAPTER 3: THE STUDY OF POTTERY SECTION B: QUESTIONS AND METHODOLOGY za CHAPTER 4: QUESTIONS AND-APPROACHES 4.1 Seriation ''. 4.2 Provenancing '4.3 Interpretation of the Site 4.4 The Usefulness of the Techniques used in the Interpretation of the Assemblage CHAPTER 5: METHODOLOGY 5.1. Excavation: Retrieval and Recording 5.2 " Clay-Survey 5.2.1 Introduction 5.2.2 Clays: Compositions and Properties 5.2.3 Clay Formation 5.2.4 Areas Sampled 69 5.3. Pottery Technology: Determination of Manufacturing Techniques 76 5.3.1 Introduction 76 5.3.2 The Clay Body 78 5.3.3 Forming 87 5.3.4 Secondary Forming 95 5.3.5 Surface Finishing 96 5.3.6 Drying and Firing 103 5.3.7 Recording System for the Pool Pottery 112 5.4 X-ray Fluorescence Spectrometry 118 5.4.1 Introduction 118 5.4.2 Principles, of XRF 118 5.4.3 The Analytical, System 120 5.4.4 Factors Affecting Quantitative Analysis 124 5.4.5 Quantitative XRF 131 5.4.6 Advantages and Disadvantages of XRF as an Analytical Technique 136 5.4.7 Sample Preparation 138 5.4.8 Calibration 144 5.5 Analysis by Inductively Coupled Plasma Spectrometry 150 5.5.1 - Introduction- - 150 5.5.2 Principles of ICPS 151 5.5.3 Sample. Preparation 153 5.5.4 Calibration 154 5.5.5 Statistical Analysis 154 5.6 Thin Section Analysis 155 5.6.1 Introduction 155" 5.6.2 Sample Preparation- 159 5.6.3 Qualitative`('Descriptive' Analysis' 161 5.6.4 Quantitative Analysis 1614 5.6.5 Textural Analysis 1'64 SECTION C: RESULTS CHAPTER 6: RESULTS' 167 6.1 Seriation 167 6.1.1 Introduction 167 6.1.2 The Neolithic Pottery 167 6.1.3 The Late Iron Age and Norse Pottery 1'82 6.2 Provenancing 190 6.2.1 Results of the Clay Survey 190 6.2.2 XRF Analysis of Clay Samples 191 6.2.3 Results of Elemental Analysis of Pottery 196 6.2.4 Summary 199 6.2.5 Thin Section Analysis 200 6.3 Interpretation of the Site 206 6.4 Problems in the Analysis of Coarse Wares 207 SECTION D: DISCUSSION AND CONCLUSIONS CHAPTER 7: DISCUSSION 212 7.1 Seriation, Morphology, Technology, Function and Change 212 7.2 Provenancing 222 7.3 Interpretation of the Site 222 7.4 Problems in the Analysis of Coarse Pottery 229 7.4.1 Factors Affecting the Analysis of Coarse Pottery 229 7.4.2 Reconciling the Evidence 236 7.5 Archaeological Implications of the Study 240 7.5.1 General 240 7.5.2 The Neolithic Phases 242 7.5.3 The Iron Age Pottery 252 CHAPTER 8: CONCLUSIONS 255 BIBLIOGRAPHY 267 ACKNOWLEDGEMENTS The first two years of my research were carried out with the support of, a grant from the Science-based Ar- chaeology'Committee of the Science and Engineering Re- search Council. The Artefact Research Unit, Royal Mu- seum of Scotland provided work-space during the latter part of the project. I , am grateful to the following for their advice and practical help: Dr Peter Harvey of Nottingham Univer- sity for advice on XRF sample preparation; Mr Mike Heyworth for sorting'out my many computing-problems and for his help in, preparing the ICPS'samples; Dr Nick Walsh of the Geology Department, Royal Holloway and Bedford'New College for provision of the ICPS facilities; Mr Mark Gillings and Dr Ian Freestone for help with the thin section analysis; Dr Raymond Lamb for information on Orcadian late'Iron Age sites; Mr Steve'Dockrill and Mr Rob Janaway for help with pho- tography and'microscopy; "Ms'Andrea Smith for help with the contextual information; Mr Roy Ritchie for in- formation on the geology of Orkney. Thanks are due to the following people'for arranging access to museum collections and excavated material ACKNOWLEDGEMENTS The first two years of my research were carried out with the support of`a grant from the Science-based Ar- chaeology Committee of the Science and Engineering Re- search Council. The Artefact Research Unit, Royal Mu- seum of Scotland provided work-space during the latter part of the project. I am grateful to the following for their advice and practical help: Dr Peter Harvey of Nottingham Univer- sity for advice on XRF sample preparation; Mr Mike Heyworth for sorting out my many computing problems and for his help in preparing the ICPS"'samples; 'Dr Nick Walsh of the Geology Department, Royal Holloway and Bedford'New College for provision of the ICPS facilities; Mr Mark Gillings and Dr Ian Freestone for help with the thin section analysis; Dr Raymond Lamb for information on Orcadian late iron Age sites; Mr Steve'Dockrill and Mr Rob Janaway-for help with pho- tography and microscopy; Ms"Andrea Smith for help with the contextual information; Mr Roy Ritchie for in- formation on the geology of Orkney. Thanks are due'to the following people for arranging access to museum collections and excavated material and providing sherds for sampling - Ms Jane Bellam (Skaill excavations); Ms Beverley Smith (Howe excava- tions); Dr David Clark and Mr Trevor Cowie of the Royal Museum of Scotland, Edinburgh; Ms Anne Brundle and Mr Bryce Wilson of Tankerness House Museum, Kirk- wall; Mr A Williamson of Shetland Museum, Lerwick; Dr Euan MacKie of the Hunterian Museum, Glasgow; Dr Coleen Batey (Freswick excavations). Access to unpublished material was provided by Dr John Hunter and Ms Ann Clarke (Pool);, Mr Magnar Dalland and Ms Ollwyn Owen (Kebister); Ms Andi Ross (Howe) and Ms Jane Bellam (Skaill). I am grateful to Ms Anna Chudecka for allowing me to use her illustrations of the Pool pottery, and to Mr Chris Burgess who drew up the XRF diagrams and the grain-size matrix.