The last frontier in 'sourcing': the hopes, constraints and future for iron provenance research

The socioeconomic importance of iron to the populations that make use of it is evidenced by the metal's incorporation into nearly every aspect of life, from domestic chores and agriculture to large scale building construction, transportation and warfare. Yet, while provenance analysis, or 'sourcing', has a long history of generating insights concerning the circulation of most other archaeological materials, iron has languished in what seems a perpetual stage of method development. The past decade, to be sure, has witnessed a flurry of new iron provenance research that displays increasing sophistication of both data acquisition techniques and statistical applications. It has also exposed divergent stances on what can or should serve as an object's potential 'source'. Practical achievements beyond localized case studies, however, are few. This paper reviews current practice in iron provenance research and evaluates it in terms of ironmaking technology and the provenance postulate. Constraints to iron provenance success are identified in the unique attributes of iron and ironmaking technology as well as some of the 'sourcing' strategies employed. Some novel approaches, however, do present opportunities to empirically evaluate longstanding models of iron production and distribution and to generate seeds for new models. The effective implementation of these emerging research programmes will require more extensive sampling of sources and efforts to ensure comparability of inter-laboratory data.