4.11 The Slags and Metal-working Debris

by Jane Cowgill *

4.11.1 Recording methods

The slag from the 1986-1992 areas was rapidly scanned and a detailed archive report was compiled for that recovered from Sites 2 and 11 (approximately 14kg in weight and 20% of the total slag assemblage). The slag was identified solely on morphological grounds and the categories used are those defined by McDonnell 1992. A database of the recorded slag has been compiled which contains the following information: Area; Context; Find Number; Slag/Material type; Weight; Comments.

A note of possible fuel types has been recorded when fragments were incorporated in the slags. Probable iron objects and pieces of ore have also been isolated.

The metal-working debris was recorded three dimensionally on site and therefore most of the bags contain single pieces; this considerably slows down the speed of recording. The total weight of the assemblage is c.75kg and much of this is composed of the characteristic small pieces that are common at this date.

Soil and environmental samples are available for study where appropriate.

4.11.2 Background information

Most the slag seen was either associated with iron smithing or was of a non-diagnostic type (for example fuel ash slag). There remains, however, the probability that iron was smelted at the site because two iron furnaces were excavated and several fragments of blooms are thought to exist. The slag associated with these features has not yet been examined. Two stone tuyeres were also found. There is only one crucible from the site, suggesting that any non-ferrous metal working at West Heslerton was extremely limited or non-existent.

Although a number of hearths have been excavated, they are generally in poor condition and it has not been possible to establish yet whether they were purely domestic or otherwise. The fired clay and 'hearth lining' assemblages have not been studied in detail. Of interest is the presence of a shaley coal and charcoal within the matrix of the slags, suggesting that both were used as a fuel for smithing. The distribution of the coal will be of interest to identify whether it was used exclusively for iron working or as a general fuel type.

The iron objects await identification so as yet it is not known whether there are any bars, blanks or part worked pieces from the site. The presence and distribution of these would help in ascertaining if a smithy is present, as would the presence of hammerscale amongst the corrosion products on the iron objects (identifiable from the X-radiographs) (see also 6.5 The Anglo-Saxon Landscape, 6.5.4 Agriculture, economy, production and exchange and 7.2.1 Environment and economy).

4.11.3 Significance of the assemblage

The likelihood of both smelting and smithing occurring on this site affords a rare opportunity to examine both the organisation and technology of the iron industry in the Saxon period. Few sites have been examined in detail and even fewer offer a large well-excavated assemblage for analysis (for discussion see McDonnell 1989). So little is known or understood about the processes at this date that it is impossible to target any particular aspect of the industry as being of greater significance than any other. The scale of the excavation and detailed recording allows an examination of spatial patterning, extent and frequency of the activities, technologies involved and any chronological changes.

Of enormous significance is the fact that two contemporary sites, both with iron working assemblages (Flixborough, Humberside, and Christ Church College, Canterbury) will be studied and analysed at about the same time, using the same methods and recording systems, so that the results will be directly comparable. The three sites appear to have very different reasons for their foundation and economic survival, allowing status comparisons to be made and the influence of the Church to be considered. Their differing locations also enable regional differences to be examined and the possibility of European influences to be tested. The site

Two metal-working furnaces were identified in the southern craft/industrial zone; this is also where the majority of the smithing slags were found. It has been suggested that these were iron smelting furnaces but this identification needs to be validated, as has the existence of the blooms. If smelting on the site can be proven, a subject to be addressed is the relationship between the smelters and smiths. It is usually assumed that the people who undertake the two operations are distinct and have identifiably different skills; however, this model has not been tested and may be proven wrong - for this period at least.

There is almost no information concerning the technology/s used for smelting iron in the Saxon period or the regional differences that appear to exist (McDonnell 1989). If the furnace type used can be identified it will add significantly to the existing slim data-set.

The quantity of slag recovered is evidence for the presence of a smithy/s on or near the excavated area; this is made all the more likely considering the fact that it is a rural site. Information concerning the possible location of a smithy should be sought through the examination of the X-radiographs of the iron objects (high concentrations of hammerscale in the corrosion products would be expected close to the smithing activity). Hammerscale has no secondary use and therefore large quantities within a defined area are considered to be indicative of a smithy. Most of the environmental samples have already been processed and so are not available for checking with a magnet, but those from the 1995 excavation and a number of soil samples are available and will be tested.

If the location of a smithy/s can be established, or confidently predicted, a wide array of questions concerning the site can be addressed. For how long was it in operation and was the workshop static through time or did it move with the settlement drift? Where is it located within the settlement and what significance may that have regarding its status? Is there any evidence for 'an industrial area' or was it intermixed with domestic dwellings? Smithing is often considered to be a craft with a high nuisance factor and therefore located on the periphery of settlements. This could be questioned in a rural context where noise (the main 'pollutant' of a smithy) may not be an important or significant factor. However, the use of shaley-coal may have increased the smoke output significantly and therefore the composition of the fuel is worth noting in the context of the smithy location.

If there is a smithy the associated features, in particular hearth type, will be important to record, as well as considerations such as whether the hearth is a specialised form, or has similarities to domestic types and to any other recognised hearths associated with other specialist functions. A stone tuyere has been recognised on the site and there is the possibility that others may exist amongst the fire clay assemblage.

Any assemblage of iron objects associated with deposits of datable slag requires careful examination for the presence of bars, blanks or any type of waste iron. Broken iron artefacts may also be present, having been collected for recycling.

There are both charcoal and ?shale inclusions within the slags. The charcoal was presumably used as a fuel source. The laminating ?shale material requires identification and sourcing and the possibility of its use as a fuel needs consideration. There are outcrops of shale close to the site so it is likely to be of local origin. If the ?shale was used as a fuel it will be interesting to examine whether it was also used in a domestic context.

Another topic that this site allows the opportunity to consider is the disposal of the slag, its movement across the site and if it had any specific re-uses (for example surfacing paths or roadways within or through the settlement). Technology

The quality of the excavation and the date range of the settlement allow exciting questions concerning the technological aspects to be answered. The morphology of the slags suggest that there is some diversity of types present and it would be worthwhile creating a simple typology of the smithing slags and to test whether this is significant through X-radiographs, and also possibly using chemical and mineral analysis. The use of X-radiographs allows a quick, simple and cheap method of examining the density of slag and the metal content. If the results were significant enough, further analysis could be considered providing the dating of the samples can be proved to be reliable.

The results could then be tested to discover if there is a temporal or spatial significance. This would allow a re-examination of the technology and methodology of iron working throughout this period, of which so little is currently known.

4.11.4 Aspects of the metal-working assemblage that require clarification through study, analysis and publication The smelting evidence: The smithing evidence: General discussion:


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Last updated: Tue Dec 15 1998