Tales of the Iron Bloomery

Bernt Rundberget, Ph.D. (2013), Museum of Natural History and Archaeology, NTNU, is Head of the Department of Archaeology and Cultural History. He has particular experience in Norwegian pre-Reformation iron bloomery and has published several papers in scientific journals and proceedings.

• Contents Preface ix List of Figures and Tables xi 1 Introduction 1 Area and Boundaries 3 Chronological Depth 8 The Evidence 10 Topics and Aims 12 Key Issues 14 Outlying Land and Its Use 16 Regions and Technological Boundaries 20 Exploiting the Landscape 23 The Economic Context of Jernvinna-Domestic Activity, Craft or Something More? 29 2 Research Backdrop 42 Status of Research 42 The Introduction of Iron and Jernvinna 44 Methods of Production in Chronological Terms 45 The Slag Tapping Furnace in Europe and Scandinavia 48 Charcoal Burning, Spatially and Temporally 69 Bog Ore and Roasting Places 76 3 Jernvinna in the Grafjell Area-Conformity in Distinctiveness 80 Introduction 80 Rolf Falck-Muus-A Major Contributor 80 Recent Surveys and Excavations 86 Bloomery Ironmaking in the Grafjell Area-Form and Facts 88 The Archaeological Investigations 98 The Slag Tapping Furnace of the Grafjell Area-A Distinct Method 118 Unexcavated Bloomery Sites 129 From Concept to Symmetrical Organization 132 Bloomery Sheds 138 Occupation or Settlement? 142 Rodsmoen and the Grafjell Area Compared 146 Charcoal Pits-From Statistical Bulk Sample to Organizational Factor 148 Roasting Places-A Factor in a Comprehensive Understanding 161 Organization and Exploitation of Resources 175 4 A Regional Tradition 183 The Source Material 183 South Osterdalen 184 Solor 196 Hedemarken 204 The Delimitation of the Hedmark Tradition 208 5 The Dating of the Hedmark Tradition 216 Introduction 216 The Bayesian Approach 219 The Summing of Radiocarbon Dates 222 Wood Species and the Dating of the Hedmark Tradition 222 Wood Species Determinations 223 Annual Growth Ring Counts and Dendrochronology 227 The Bayesian Approach-Precise Dating of the Period of Use 230 The Grafjell Area-a Specific Chronology 240 14C Dates at Rodsmoen 242 The Dating of jernvinna in Hedmark 243 6 The Volume of Production from the Hedmark Tradition 249 Calculations of the Volume of Slag Heaps 249 Calculations of Volume of Slag 252 Calculations of Yield 253 The Volume of Charcoal Production 255 The Volume of Iron Production 257 The Consumption of Raw Materials and Yield 266 Volume and Period of Use 269 The Volume of Iron from the Hedmark Tradition 271 The Volume of Production through Time 273 7 The Study Area in the Light of Archaeological and Historical Sources 276 Settlement and Its Development 276 Hunting 292 The Written Sources 296 8 Tales of the Iron Bloomery 319 The Technological Concept and Coordinated Activity 319 Methods in the Borderland 321 The Hedmark Tradition in Time and Space 336 Specialized Work 342 Proto-industrialized Bloomery Ironmaking-the Unknown Economy of Osterdalen 346 De-industrialization-the Collapse of the Tradition 351 9 The Economic Role of Iron in an Inter-regional Perspective 361 Appendices 368 Appendix Ia: Bloomery sites excavated in the Grafjell area - data and interpretation 368 Appendix Ib: Excluded bloomery sites, not archaeologically investigated 378 Appendix IIa: 14C-datings and dendrochronological datings from the Grafjell area 387 Appendix IIb: Excavated and dated bloomery sites of the Hedmark tradition 405 Appendix IIc: Excavated and dated charcoal pits of the Hedmark tradition 414 Appendix III: Calculation of volume and estimation of weight of slag in slag heaps 426 Bibliography 443 Primary Sources 443 Secondary Sources 443 Internet Sources 473 Index 474