Spatial patterning of Early Iron Age metal production at ...

Journal of Archaeological Science 31 (2004) 1511e1532 http://www.elsevier.com/locate/jas

Spatial patterning of Early Iron Age metal production at Ndondondwane, South Africa: the question of cultural continuity between the Early and Late Iron Ages Haskel J. Greenfielda,), Duncan Millerb a

Department of Anthropology, University of Manitoba, Fletcher Argue 435, Winnipeg, MB R3T 5V5, Canada b Department of Archaeology, University of Cape Town, Rondebosch 7701, South Africa Received 8 December 2003; received in revised form 13 March 2004

Abstract The spatial relations of metal working areas and domestic areas in Early Iron Age sites are important because they have implications for models of continuity and change in the southern African Iron Age. Metal working remains recovered during the 1995e1997 field seasons at the Early Iron Age site of Ndondondwane (AD 650e750) offered an opportunity to quantify the distribution of metal working activities. Metal working residues were classified visually, the distribution of various classes of remains plotted, and selected samples analyzed metallographically to confirm the visual identifications. This study revealed the marked spatial and temporal distribution of ore preparation, primary iron smelting, and secondary forging activities on the site. In the earliest of three identified occupational horizons, relatively sparse metal working remains were associated with forging activities near hut floors in the centre of the site. In the intermediate occupational horizon, metal working on the site was confined to ore preparation and forging in the vicinity of the more peripheral domestic areas associated with middens. Any smelting must have been performed elsewhere. In the final occupational horizon, metal working was concentrated in the central area again, where the remains of a furnace and a dump containing about 500 kg of slag attest to primary iron smelting. The implications of this temporal and spatial distribution for models of site organization in the Early Iron Age are discussed, and are indicative of greater cultural continuity in metal production between the Early Iron Age and later periods in the region than hitherto believed. Ó 2004 Elsevier Ltd. All rights reserved. Keywords: South Africa; Early Iron Age; Smelting; Forging; Iron; Slag; Spatial distribution of activities

1. Introduction The spread of the earliest food producing communities occurred relatively late in prehistory in southern Africa in comparison with elsewhere on the continent. The appearance of food producing communities in eastern southern Africa occurs simultaneously with the introduction of iron metallurgy (contrary to western southern Africa) [21,45]. Both food production and early iron metallurgy appear during the Early Iron Age (EIA, i.e. 1st millennium AD) of the region. It has been argued that the EIA arrived in southern Africa as an ) Corresponding author E-mail addresses: [email protected] (H.J. Greenfield), [email protected] (D. Miller). 0305-4403/$ - see front matter Ó 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.jas.2004.03.014

economic and social package e which included iron smelting, ceramic technology, and mixed pastoralfarming economies. Small sedentary village communities were located in river valley environments, and organized into loose regional political entities comprised of a few villages (located a few kilometres apart) under the hegemony of a hereditary chief [13,25,27,35,42,47]. The appearance of these communities in southern Africa initiated an evolutionary trajectory that eventually culminated in the complex societies of the Late Iron Age (LIA) and historic (precolonial) periods [4,12,16,44,46]. Until recently, most research on the EIA of southern Africa has focused upon defining the culture historic sequence of communities in the region. As a result, the general outlines have been defined, at least in certain

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H.J. Greenfield, D. Miller / Journal of Archaeological Science 31 (2004) 1511e1532

regions like KwaZulu-Natal [24e27,40,41,43,49], but relatively little effort was expended to reconstruct EIA social and economic organization. This began to change in the late 1980s with the beginning of the still on-going discussion in southern African archaeology concerning community organization. As part of this debate, two largely contradictory models have been proposed to explain the nature of EIA community organization. At one end of the spectrum, Hall argued that EIA communities were organized at what is known in the anthropological literature as a household or domestic level of production [6,13,36,38]. At the other end of the spectrum, Huffman [15,18e20], Denbow [2], Whitelaw [48] and others have argued for more community-wide modes of production (based on ethnographic models originally proposed by Kuper [22] for the spatial organization of settlements of present-day and historically recent SE Bantu-speakers), typically known as the Central Cattle Pattern. This has been somewhat resolved in favour of the latter model as spatial data from a small number of sites have been garnered in support [8e11,43,48]. An even longer running discussion has concerned the issue of cultural continuity between the EIA and LIA periods. Most archaeologists have recognized changes in ceramic signatures (types and motifs) as signalling dramatic cultural and hence population shifts in the region. The evidence for metallurgical production has often been marshalled in support of this hypothesis. It has been argued that there is a shift in the locus of metal smelting from on- to off-site locations [34,39,48], with concomitant implications for the visibility of smelting and associated ritual activities. Yet, the data in support of the Central Cattle Pattern model demonstrate that the community organization patterns found in the Ethnographic and LIA periods also extend back into the EIA. This implies greater continuity than heretofore suspected. The EIA site of Ndondondwane (South Africa) provides the opportunity to assess the similarity or difference in spatial patterning of metal working activities in the EIA and the LIA periods, and in so doing test the validity of employing the Central Cattle Pattern as a model for the interpretation of settlement layout in the EIA. In this paper, we study the location of metal smelting and forging activities over time at Ndondondwane, which is appropriate for such a test because of its extensive investigation and tight spatial and chronological controls. The results are part of our long-term contribution to the discussion on the nature of EIA social and economic organization.

2. The site location The Lower Thukela river basin of KwaZulu-Natal province, South Africa (Fig. 1) is an appropriate region

for studying EIA settlement patterning because research in the area has yielded one of the most comprehensively defined regional EIA culture historic sequences [24,25,27,28]. The EIA ceramic sub-phasing is anchored by radiocarbon dates with a very narrow temporal range (100e150 years), allowing strict control over temporal variability within the region. This level of control is available in only a few other areas of the subcontinent [2,3,17]. The EIA site of Ndondondwane (28(53#S, 31(01#E) is situated in the Middledrift area of the Thukela River valley (Fig. 1), between the confluences of the Nsuze and Wosi rivers, in KwaZulu-Natal (South Africa). The site has been studied by various teams of researchers over the past 20 years [10,11,23,26,43]. Ndondondwane is the name site for EIA ceramics of this period in KwaZuluNatal [26]. Uncalibrated radiocarbon dates from the site indicate an occupation in the range of AD 650e750, which when calibrated cluster ca. AD 879e892 (G50 years, 1 sigma) [50]. A comprehensive surface and subsurface reconnaissance program [11], as well as extensive excavation and areal sampling, produced large quantities of archaeological material. These include not only characteristic ceramic pot sherds, but also fragments of sculptured ceramic heads [23], as well as very large volumes of iron smelting and working debris. The iron working residues were classified visually and plotted spatially to study their distribution. Presumed ore fragments, large quantities of slag, and the few metal artefacts collected during the 1995e1997 field seasons were submitted to the Archaeology Materials Laboratory at the University of Cape Town for confirmatory analysis. This study was aimed at identifying the nature and location of specific metal working activities, such as ore preparation, smelting and forging, on the site, characterizing the processes that were undertaken by the metal workers, and interpreting these results in the light of the emerging temporal sequence of occupation at Ndondondwane.

3. Site layout and major features related to metal working Systematic survey, excavation, and sampling of Ndondondwane have identified a number of distinct activity areas arranged in a semi-circular area on the eastern river bank (Fig. 2). The site can be divided into central and peripheral activity zones [7e11,23,43]. The central zone consists of a ‘central’ Mound Area connected stratigraphically to a Dung Area some 60 m to the north. The central zone is closest to and parallels the river’s edge and is surrounded at a distance of about 100 m by an arc of domestic and special activity areas, extending from north to south: Domestic Middens 1, 2, and 3, and the Charcoal Preparation Area.


Fig. 1. Map of lower Thukela river valley (inset KwaZulu-Natal coast).

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2. that there are small stylistic (but not technological) differences between the Lower and Middle Cultural Horizons, and 3. that there is no perceptible change in ceramic decoration or technological style between the Middle and Upper Cultural Horizons.

Midden 3

100.00

Midden 1

50.00

Dung Area

0.00 Transect 1

-50.00

Transect 2

Mound Area

Midden 2 (formerly Daga Midden)

-100.00

Charcoal Preparation Area

South end of Midden 2 (Formerly called Midden 4)

-150.00

-200.00

-50.00

Pump House

0.00

50.00

100.00

Fig. 2. Distribution of excavation and surface collection units (centre points) at Ndondondwane.

Comprehensive augering across the site and adjacent areas, and targeted excavation revealed a pan-site stratigraphy consisting of five horizons; from a sterile base at a depth of about 65 cm, through three cultural horizons (Lower or 1, Middle or 2, and Upper or 3), sandwiched between a surficial plow zone and a sterile substrate. The strata were differentiated on the basis of superposition, colour, and texture. With the use of hand augers, strata identified in excavation areas were traced across the intervening spaces to neighbouring trenches. All three cultural horizons are represented in the central zone, but most of the deposits in the peripheral arc were incorporated into the plow zone. Enough remained to link the deposits of Middens 1, 2 and 3 stratigraphically to the Middle Cultural Horizon, and the Charcoal Preparation Area to the Upper Cultural Horizon. This has been confirmed by Fowler’s micro-seriation [5] of the ceramics from the site. It demonstrates the following: 1. that all three horizons belong to the Ndondondwane ceramic phase of the region,

This is interpreted to indicate that only a very short time has passed between the formation of the Lower and Middle Cultural Horizons, and almost none between the Middle and Upper. The relationship between the Lower and Middle Cultural Horizons is supported by the two radiocarbon dates from the site [26,50]. These derive from the two lower cultural horizons of the Mound Area and date to AD 879 for the Lower and AD 892 for the Middle Cultural Horizons (calibrated, Table 1). No radiocarbon dates exist from the uppermost horizon (CH 3). No further radiocarbon dates from the site are available yet. The Mound Area is located at the south end of the central zone and was associated with the remains of ivory working, ritual in the form of numerous clay mask fragments, and iron production, the latter in the form of remains of a slag-lined bowl interpreted as a furnace and a large slag dump. Given our re-analysis of Loubser’s excavation data from the Mound Area, his five laterally displaced activity areas [23] can be assigned to the three cultural horizons, of which furnace and smelting material were recovered from only the uppermost. In the Upper Cultural Horizon, the northern side of the mound contained ceramics, furnace daga blocks, tuyere fragments and an estimated 300 l (ca. 500 kg) of slag, while a slag-lined depression 4 m to the south of the dump was probably the base of the furnace structure [23]. The notional reconstruction of the furnace from these remains is important, because EIA furnaces all appear to have been broken down to ground level and the remains discarded [34]. ‘‘The blocks are mostly quadrilateral and are between 70 mm and 100 mm thick. They are lumpy on the exterior, while their interior surfaces are often striated with deep finger-like impressions. A crust of glassy slag is attached to the interior surface of some blocks. Using all the daga from the slag and daga concentration, I could reconstruct two vents. Each had an external diameter of 90 mm and in internal diameter of 100 mm, indicating that they had a spout-like shape widening towards the interior. Because Table 1 Radiocarbon dates from Ndondondwane (cf. [5,50]) Lab. no. Uncalibrated age

Calibrated age range

Cultural Age bp Age AD SD Min. Midpoint Max. Horizon

Pta-2388 1220

730

50

Pta-2389 1190

760

50

790 919 867

879 e 892

905 951 974

Lower Lower Middle


remnants of the two vents came from opposite sides of the elongated rubble heap the two vents could have been on opposite sides of the furnace’’ [23]. A second major activity area in the central zone was a large burnt hut floor, with a possible hearth in its centre (Transect 1). Upper and lower flat grindstones were found, none of which had the characteristic groove for grinding sorghum [39]. A large quadrilateral stone with a flat polished surface, possibly used in working or sharpening iron tools, was found in the centre of the hut. The hut floor was stratigraphically linked to the Lower Cultural Horizon. A third activity area in the central zone was a livestock enclosure named the Dung Area, found at the northern end of the central zone. This contains a zone of human activity, including evidence of iron forging in the form of slag concentrations, charcoal deposits, and forge hearths, and a zone of animal husbandry, filled with thick deposits of dung. All three cultural horizons were evident in the Dung Area, but evidence of iron forging was found only in the Lower and Middle Cultural Horizons. There is no evidence for fencing around the forging loci. A fence was only identified around the livestock part of the Dung Area (Lower and Middle Horizons) and in the Mound Area (Middle Horizon). Based on conductivity survey, excavation, and augering, the space between the Dung and Mound Areas, and between the central and peripheral activity zones was devoid of large features. Additionally, a gap of about 100 m separated the Dung and Mound central area from a peripheral arc of middens to the east [11]. The peripheral middens were associated with domestic debris, hut floors and pits containing accumulations of bone, ash, pottery, grindstones, and in one instance an infant burial. Extensive survey and auger sampling in intervening areas demonstrated convincingly that occupational debris was concentrated in the identified areas. Stratigraphically, each of the domestic middens was linked to the Middle Cultural Horizon. At the southern end of the ring of peripheral activity areas, and 70 m to the south of the Mound Area, there was a deposit which is interpreted to be a charcoal preparation area. It contained numerous ceramics and large quantities of charcoal lumps. Stratigraphically, this deposit is linked to the Upper Cultural Horizon. Another concentration of smelting debris, including daga fragments and large blocks of partially fused ore cemented with slag, was found near the modern pump house, a further 70 m to the south of the Charcoal Preparation Area ( first noticed by Loubser [23]). Extensive investigation of the southern end of the surface debris by Greenfield and van Schalkwyk’s team repeatedly failed to yield any evidence of in situ furnace or smelting debris [8e11,43]. Discussions in the 1970s that were reconfirmed in 2001 with the head of the local farming family (Campbell Woolmore) led to the

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conclusion that this was a heap created by recent farming activities in clearing plowed areas of large obstructive blocks (T. Maggs, pers. commun. 2003). In sum, it appears that the site was occupied initially during the Lower Cultural Horizon, with a large hut in Transect 1, a smaller hut in the Mound Area, and a substantial activity area in the Dung Area (including a livestock enclosure and an associated human activity area with iron forging and other activities taking place). The rest of the site is uninhabited during this horizon. During this phase, the site is quite small, limited to the centre (ca. 100 m from N-S and 80 m E-W). In the Middle Cultural Horizon, the large hut in Transect 1 is abandoned and this area becomes empty space, with a large tree growing in the centre. The Mound Area becomes a centre for initiation, ivory working, and other activities, much of which is sealed off from public view by a fenced enclosure. The livestock enclosure in the Dung Area shifts slightly (1e2 m) and the associated human activity area shrinks in size, with fewer definite associated activity areas. The biggest change is the appearance of three domestic midden complexes (1e3) around the eastern periphery of the site. Each is associated with a hut, granary storage (above or below ground), hearths, ash dumps, and middens. This is the phase of maximum spatial extent of the site (ca. 200 m N-S and E-W). In the Upper Cultural Horizon, the outer ring of domestic complexes is abandoned. All of the grindstones at the site are gathered up and dumped into a single large storage pit (Pit 2) in Midden 1. Major changes take place in the Dung Area with the abandonment of the livestock enclosure and the dumping of a large quantity of very fine ash. Domestic activity in these areas ceases. The same is true for the Mound Area, where the only evidence of activity is the presence of a smelting furnace base and a large slag pit. The Charcoal Preparation Area at the south end of the site appears during this horizon. Effectively, this horizon signifies the abandonment of the site and its post-occupational use for smelting. Confirmation of the field assessment of metal working loci and remains requires the physical and chemical analysis of representative samples, and the assessment of the results of the archaeometallurgical study in terms of the local geology and archaeological associations. These are presented in the remainder of the paper.

4. Local geology The site is located on the eastern bank of the Thukela River (Figs. 1 and 2), on a fertile terrace underlain by Pleistocene sediments, calcrete, and a cobble filled palaeo-stream channel. The local country rock consists of the various mafic and felsic tectonites of the Tugela

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terrane. The area around Middledrift is underlain by alternating layers of amphibolite and grey gneiss, and forms part of the Dondwana Tectonite Unit (of the Mandleni Tectonostratigraphic Package). The amphibolite is a dark rock containing hornblende, plagioclase, diopside, and quartz, often with epidote and sphene; while the lighter gneiss consists of plagioclase, quartz, and biotite, sometimes with hornblende [1]. There are several distinct potential sources of the metamorphosed banded ironstone ore found at Ndondondwane. In the Middle Ecca Group of the Karoo System, exposed northwest of the Tugela terrane, calcareous ironstone deposits have been intruded by Karoo dolerites, and undergone contact-metamorphism to produce haematite/magnetite rocks. In the first half of the 20th century these were worked for the blast furnace at Newcastle in the northeast of the province [14], but there are much closer potential sources of ore from the metamorphosed banded ironstones within the Tugela terrane itself. Although no banded ironstones were recorded by Bisnath [1] in the immediate vicinity of Middledrift, the geological map of Matthews and Charlesworth [30] shows numerous sinuous outcrops of ‘magnetic quartzite’ in the surrounding amphibolites. Magnetite ore is exposed on the south bank of the Thukela river at the nearby site of Wosi [41], and there is a more distant potential source of magnetite ore near the site of Mamba, about 6 km to the south [40]. The most proximal source at Wosi is the most likely source of ore for Ndondondwane.

5. Nature of metal working remains 5.1. Method All the suspected metal working remains recovered in the 1995e1997 field seasons were weighed and sorted by visual appearance and magnetism, and selected samples were analyzed petrographically or metallographically. Pieces of country rock, including amphibolite and micaceous schist fragments, were identified by eye and petrographically. Metal production waste was classified in ten categories. Ore fragments consisted of metamorphosed banded ironstone in blocky pieces, a few centimetres square, representing raw ore. Many pieces were partially reduced, strongly magnetic, with coatings of slag, or adhering to each other with intervening slag, and were classified separately as slag covered ore. These graded into larger slag nodules retaining some of the original blocky shape of the ore, with partially reduced pieces of ore embedded in them (Fig. 3). The latter could be ascribed confidently to smelting activity and along with blocks of only slightly vesicular, greenish slag were classed as smelting slag. Seven distinctive objects were classified as forge bases. These were round to oval buns of slag, palm-sized, and plano-convex in section, with undulating upper surfaces showing fluid structures, and rougher lower surfaces with the impressions of numerous small charcoal fragments (Fig. 4). The distinction between forge bases and smelting slag was made purely on external morphological appearance. The class of

Fig. 3. Photograph of slag blocks (NDOS52) from Ndondondwane, containing only partly reduced chunks of ironstone ore (scale divisions 10 mm).


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Fig. 4. Photograph of the top surface of a plano-convex forge base (NDOS42) from Ndondondwane (scale divisions 10 mm).

tabular slag comprised plate-like slag fragments, often with undulating upper surfaces and sandy bases. Both these and glassy slag, which were characteristically frothy, were ascribed tentatively to forging activity, although they could also represent smelting. Slagged ceramics were separated into slagged tuyeres represented by fused tips, and slagged furnace lining consisting of larger bloated ceramic fragments with a slag coating on

one side. A class of indeterminate slag included all the slag which could not be assigned with confidence to any of the other classes. Many of these were visibly inhomogeneous. On analysis two slag samples transpired to be very corroded remnants of iron bloom, but there could have been more of these in the indeterminate slag. Metal artefacts, mostly very corroded remnants of iron in the form of small rusty flakes, made up an eleventh class (Fig. 5).

Fig. 5. Photograph of remnants of iron artefacts from Ndondondwane, with NDO1, NDO3, NDO4, and the six fragments of NDO6, from left to right (scale divisions 10 mm).

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formation, which is not necessarily indicative of very rapid cooling by quenching [37]. The pointed shape was undoubtedly fortuitous. Given the severe corrosion of most of the iron it was impossible to determine the original function of this object, but it must have been part of some large implement like a hoe or hammer head. The two remaining iron objects sampled were fragments of iron blades (NDO3 and NDO6). These were very corroded with almost no metallic iron left. The residual metal and pseudomorphic ‘ghosts’ of elongated inclusions preserved in the corrosion products indicated that the blades consisted of bloomery iron which had been hot worked. A small patch of uncorroded metal in NDO3 had a carbon content of about 0.3%, and a Widmansta¨tten structure indicating fairly rapid air cooling from a temperature in excess of about 800 (C. These items were similar to iron artefacts from the EIA site of KwaGandaganda [34] and quite typical of African bloomery iron production.

5.2. Metal artefacts There were few metal artefacts, and many of these were undoubtedly modern e a brass bullet casing, fragments of cast iron pot, and a can opener, which were part of the surface collections. Five iron artefacts were sampled and prepared for metallography using standard techniques (Table 2; Fig. 5). Two fragments of cast iron (NDO4 and NDO24) were probably broken fragments of domestic cooking vessels. Both consisted of very fine grained, homogeneous, high carbon, grey cast iron, typical of early 20th century production. The only substantial iron artefact (NDO1) was a pointed mass, roughly awl-shaped but very corroded, weighing 47 g (Fig. 5). It consisted of banded bloomery iron with oxide scale trapped in poorly executed welds where the metal had been folded over to thicken the section (Fig. 6). The metal contained typical stringers of two-phase bloomery iron inclusions, and a variable carbon content ranging from 0 to 0.7%. It also contained patches of martensite, a transformation product usually associated with quenching. It is rarely encountered in indigenous iron [32], but the high carbon content in places in this artefact promoted martensite

5.3. ‘Ore’ samples Many of the pieces of the banded ironstone classified as ‘ore’ were palpably attracted to a small horseshoe

Table 2 Metallographic descriptions of iron artefacts from Ndondondwane Object

Structure

Constituents

Alloy

0e0.7%C Ferrite bands alternating with high carbon bands, martensitic, bloomery iron NDO3, dung (E) Very corroded, Ferrite and w0.3%C T6, iron small residual pearlite blade patch in a fragment, of iron Widmansta¨tten 2.7 g structure, bloomery iron 3e4%C NDO4, pump Very fine Graphite house 1/ grained cast iron rosettes, 2M,R,W, iron ferrite, pearlite, plate steadite, cast iron fragment, 4.7 g NDO6, dung E Almost Corrosion Cannot be U1, iron completely product, determined blade fragment, corroded, with bloomery iron 9.4 g tiny spots of metallic iron NDO1, dung area R7, iron ‘awl’, 47.0 g

Banded, very inhomogeneous, folded over with poor welds

Graphite NDO24, surface Very fine collections, grained cast iron rosettes, ferrite, iron pot pearlite, steadite, fragment, cast iron 247.6 g

3e4%C

Grain size

Inclusions

Ferrite ASTM 4e6, aust. ASTM 3

Slag stringers Folded over, with 2 phase poor welds inclusions, oxide trapping oxide scale in welds

ASTM 7e8

Elongated single None visible phase glassy inclusions

e

Tiny angular sulphides (?)

None

Cast iron

Cannot be determined

Ghosts of elongated glassy and 2 and 3 phase bloomery inclusions Tiny angular sulphides (?)

Cannot be determined

Hot worked

None

Cast iron cooking pot

e

Deformation

Fabrication Hot worked, folded over and welded to thicken section, normalized, rapid cool/quenched? Hot worked, normalized, rapid air cool

Object: catalogue number, grid co-ordinates, depth, classification, metal. Structure: form, external appearance, general internal structure. Constituents: metal phases and textures, metals analysis. Alloy: visual estimation of %C from standard charts. Grain size: visual estimation from ASTM grain size charts, aust.: former austenite grains. Inclusions: orientation, general appearance, identification. Deformation: microstructural evidence of hot- or cold-work. Fabrication: identifiable steps in fabrication technology.

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Fig. 6. Micrograph of a polished and etched section, viewed in reflected light, of a pointed iron remnant (NDO1), showing typical compositional banding due to folding and poor welding of bloomery iron (magnification 14!).

magnet, indicating that they contained magnetite. Most of the others obviously were also banded ironstones, so presumably they consisted predominantly of haematite, which is not magnetic. Six ‘ore’ specimens were selected for analysis. Five were banded ironstones, three of them weakly magnetic (NDO5, NDO16, NDO22) and two strongly magnetic (NDO13, NDO34). The sixth sample (NDO38) was a greenish rock, initially suspected to be possible copper ore (L. van Schalkwyk, pers. commun. 2002). All six samples were studied petrographically in thin section in both transmitted and reflected light. The five banded ironstones were all mineralogically similar, differing only in the relative proportions of their mineral constituents. All the banded ironstone samples had undergone geological thermal metamorphism, allowing recrystallization and the growth of metamorphic minerals such as garnets. In the weakly magnetic specimens there was a preponderance of haematite over magnetite, the haematite characterized by its higher reflectivity, birefringence, and lamellar twinning. The magnetite was pinkish brown, isotropic, often with crystallographically orientated inclusions of haematite, and more altered by partial weathering. These weakly magnetic samples were represented by the XRF analysis of NDO22 (Table 3). The analysis was relatively silicarich (20.5% SiO2). With much higher grade ore available, this particular sample probably represented discarded material. The strongly magnetic samples had a large preponderance of magnetite and were samples of high grade ore. The metal oxide crystals formed layers with larger or lesser amounts of silicate grains. These consisted predominantly of colourless quartz in some samples, and of pinkish garnet in others, but both

minerals were present in all samples. None of these grains were detrital and all had been recrystallized. The quartz grains were usually single grains, but intergrown masses did occur. The garnets often were euhedral and zoned, many with concentric layers of haematite inclusions. In places the garnet had been altered to patches of chlorite. Some bands contained elongated laths of the amphibole actinolite. These more strongly magnetic high grade samples were represented by the XRF analysis of NDO34 (Table 3). The XRF analyses clearly reflect the differences in mineralogical composition between the lower grade and higher grade ores. Sample Table 3 X-Ray fluorescence analysis of selected ores and slag from Ndondondwane Sample NDO22 NDO34 NDOS44 NDOS52 NDOS58 NDOS165 19.483 0.250 5.054 76.232 0.191 0.454 2.128 0.305 0.352 0.966 0.008 0.002 0.019

11.686 0.327 3.229 74.236 2.679 1.553 10.002 0.115 0.200 0.359 !0.001 0.006 0.010

15.265 0.356 3.971 76.387 3.481 1.388 3.854 0.024 0.196 0.339 !0.001 0.004 0.007

19.155 0.255 4.964 77.117 0.232 0.656 1.805 0.313 0.481 0.804 0.008 0.001 0.011

H2OLOI

0.702 0.074 0.237 2.036 ÿ0.849 ÿ5.301

0.191 ÿ4.447

0.048 ÿ4.703

0.356 ÿ5.628

Total

99.140 100.318 100.380

100.147

100.617

100.530

SiO2 TiO2 Al2O3 Fe2O3 MnO MgO CaO Na2O K2O P2O5 SO3 NiO Cr2O3

20.489 0.556 0.296 0.100 5.346 0.539 53.358 95.434 14.564 4.382 0.233 !0.084 1.675 0.012 !0.143 !0.102 0.041 0.003 0.381 0.061 !0.003 !0.004 0.012 0.002 0.007 0.004

Note that all the iron oxide has been calculated as Fe2O3 for the sake of comparison. The results are in weight percent.

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Fig. 7. Micrograph of a polished section, viewed in reflected light, of a slag nodule (NDOS23), showing primary wu¨stite dendrites (white) in a matrix of fayalite laths (medium grey) and glass (dark grey), with bright spots of metallic iron (magnification 112!).

NDO22 had much higher SiO2, Al2O3 and MnO values, which account for the larger proportions of quartz and garnet. Sample NDO34 obviously had a much higher proportion of iron oxide, with less plentiful silicates. It is noteworthy in terms of possible fluxing (discussed below) that both samples had relatively low CaO values. The non-magnetic green rock (NDO38), of which there were several pieces, was a coarse grained amphibolite consisting of an intergrowth of dark green fibrous hornblende, diopside, epidote, sphene, very sparse quartz, and large plagioclase felspar crystals with small calcite inclusions. This rock was a piece of the local country rock, the Wozi1 amphibolite of the Dondwana tectonite, and the most common rock type in the Middledrift area [1]. The mineralogical composition including diopside (nominally Ca(MgFe)Si2O6) reveals that it is a calcium-rich rock, and probably the main contributor of calcium to the slag. 5.4. ‘Slag’ samples The 14 ‘slag’ samples analyzed were chosen to represent the visible range of variation of the assemblage and studied microscopically to verify and supplement the visual identifications. Under the microscope it was evident that indeed a wide range of materials was represented. One sample (NDOS121), a very irregular rounded nodule, transpired to be a piece of burned 1 Wosi and Wozi are two alternate spellings for the some location. The spelling distinguishes the geological from the archaeological context. Wosi is used in the literature to describe the archaeological site and the nearby river. In contrast, the geological material is known as Wozi.

bone. This only superficially resembled a slag, and there is no reason to assume that it was related to any metallurgical activity. Hence, it alone cannot be taken as evidence that bones were added deliberately as a calcium-rich flux. There were two fragments of completely corroded iron bloom nodules (NDOS7 and NDOS174). Both of these were highly magnetic, with a characteristic rusty crust on the outside, unlike the glossy surfaces of most of the other slag. Both bloom nodules had adhering slag, consisting of wu¨stite dendrites in a matrix of fayalite and glass. While the main masses of bloomery iron had corroded almost completely leaving only the most minute vestiges of metallic iron in a haematite matrix, small metallic iron droplets were preserved in the adhering slag, due to the protective effect of its relatively chemically inert nature. These nodules of unworked iron bloom may have been discarded when emptying out a smelting furnace, or may have been knocked off a larger bloom along with the unwanted smelting slag. The slag attached to the iron bloom fragments was indistinguishable from a number of the other more massive slag samples which were either not magnetic, or only weakly magnetic (NDOS23, 44, 165). These slags were all fairly homogeneous, and contained primary wu¨stite dendrites in a matrix of fayalite and glass, with a scatter of small droplets of metallic iron (Fig. 7). They were all similar in composition (e.g. Table 3: NDOS165) to typical bloomery iron smelting slag, and no different from the uniform slag (GAND23 and 24) identified from the EIA site of KwaGandaganda in the Mngeni river valley [34]. Sample NDOS44 was part of a bunshaped slag cake with a mass of 566 g, identified as

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100.00

600 50.00 550 500

Dung Area Forge/smithy

450

0.00

400 Transect 1 Burned hut

350

-50.00 300 250 200

-100.00

150 100 -150.00 50

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Fig. 8. Contoured plot of all metal and slag material in the Lower Cultural Horizon at Ndondondwane (scale represents total mass in grams).

a forge base and one of several with identical external morphology (Fig. 4). It was plano-convex, with a very rough curved lower surface, covered with the impressions of numerous pieces of charcoal. The upper surface was smoothly convoluted. This slag cake cooled on a bed of charcoal, probably in a forging hearth. The sample, taken from one side, was a non-magnetic, vesicular, uniform slag, consisting of wu¨stite dendrites, fayalite laths, interstitial glass, and scattered droplets of metallic iron. The chemical composition was unremarkable (Table 3). Such forge bases consist of smelting slag which had melted in the forge, dripping off the heated bloom to form a puddle in the charcoal of the forge hearth. A further contribution to this may have been

oxidized flakes of iron scale reacting with the sand in the hearth to form fayalite. These characteristically shaped forge bases cannot be distinguished from smelting slag on the basis of chemical or metallographic analysis. Four of the slag samples analyzed contained strongly magnetic magnetite-rich nodules (NDOS52, 58, 71, 82; Fig. 3). They all consisted of either only partly reacted ore nodules,orcontainedorenoduleswhichhadundergoneonly partial reduction. This is evidence of relatively inefficient smelting, pointing to overloading the furnace with ore relative to charcoal, or to poor control over the air flow and hence reactive gas composition. These nodules were characterized by dense areas of magnetite grains, often interspersed with unreacted quartz. In some cases, the

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Midden 1 Forge 50.00

280 260 240 220

0.00

200

Intrusive slag from dump in horizon 3

180 160

-50.00 140 120 100 -100.00 80 60 40 -150.00 20

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Fig. 9. Contoured plot of all metal and slag material in the Middle Cultural Horizon at Ndondondwane (scale represents total mass in grams).

magnetite had been partially reduced to wu¨stite, and then overgrown with secondary magnetite, due to fluctuating conditions inthe furnace.As theseslags containedpartially reacted ore nodules, they could be associated with smelting withconfidence.BothNDSO52andNDOS58hadelevated calcium contents (Table 3), with NDOS52 containing 10% CaO, which accounted for the presence of augite in this sample.Theslagwasrelativelylowinphosphorus,andthere is no evidence that bones were added deliberately as a flux. The calcium in this slag probably derives from the country rock, either in the form of deliberately added sand or as melted furnace lining. Two specimens represented fusion of a ceramic with slag. Sample NDOS146 was an irregular greenish-blue,

glassy nodule. In section, it was very vesicular, consisting mainly of brown glass. This had inclusions of variably reacted and altered felspar and diopside grains. This was a piece of vitrified furnace lining, containing sand grains derived from the local diopside/hornblende amphibolite (like NDO38), which had fused with a piece of slag. This supports the interpretation that the elevated calcium in the slag derives from the diopsiderich sand. NDOS40 was a fragment of a slagged tuyere tip. The red clay body of the tuyere was coated on the outside by a black glassy slag, which had penetrated about a third of the way into the fabric of the ceramic. The ceramic was obviously made from local clay because it contained the same mineral composition as

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550 500 450 Mound Area: Furnace

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50

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Fig. 10. Contoured plot of all metal and slag material in the Upper Cultural Horizon at Ndondondwane (scale represents total mass in grams).

the local amphibolite rock, in addition to some possibly detrital magnetite. Two of the indeterminate slags analyzed were very wu¨stite-rich (NDOS35, 98). They were both relatively inhomogeneous, with varying dendrite size and varying proportions of iron oxide to fayalite. Similar slag nodules from the EIA site of Divuyu were interpreted as forging slag [31]. This was based on the less homogeneous nature of these slags, and their being more iron oxide-rich with less silicate in the form of fayalite and glass. This diagnosis is probably incorrect. Forging slag is exposed to oxidizing rather than reducing conditions, and one can expect a preponderance

of magnetite rather than wu¨stite. Nevertheless, because smelting and forging slag grade into each other, it is usually not possible to distinguish them on the basis of chemical or metallographic analysis alone [32]. They must be interpreted in conjunction with other metal working residues, such as a smelting furnace or forge remains. 5.5. Discussion of the technical significance of smelting and forging remains The local country rock, the Wozi amphibolite, was represented in the analyses by the greenish nodule

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12

50.00 11 Dung Area: forge

10 9

0.00 Transect 1: burned hut

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Fig. 11. Contoured plot of raw ore in the Lower Cultural Horizon at Ndondondwane (scale represents total mass in grams).

(NDO38). Sand derived from the Wozi amphibolite played several roles in the iron smelting operation at Ndondondwane. Sand grains weathered from the amphibolite were identified in the ceramic of the slagged tuyere (NDOS40). This amphibolite is distinctive and the local geology is very variable [1], so the source of clay for making the tuyere must have been local. Partially reacted diopside grains were found in the slag nodule interpreted as a vitrified remnant of the furnace lining (NDOS146). In this case, the calcium from the diopside-rich sand, used as a flux, promoted the formation of the glass. The chemical analyses provide further evidence for the addition of the local sand as

a flux. All of the slag analyzed had higher CaO levels than the two ore samples, and very much higher SiO2 levels than the high grade ore nodule NDO34. If NDO34 represents the grade of ore used, then the addition of a flux would have been necessary to produce slag of these compositions. This could have been in the form of some addition of the lower grade silica-rich material, but that would not account for the higher levels of CaO detected in the slag. The use of sand from the local calcium-rich amphibolite is consistent both with the observed mineralogy and the bulk chemistry of the slags, including those containing only partly reduced ore nodules.

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Midden 3

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50.00 50 Midden 1 45

0.00 40 35

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Fig. 12. Contoured plot of raw iron ore in the Middle Cultural Horizon at Ndondondwane (scale represents total mass in grams).

The ore for the iron smelting operation was a high grade, metamorphosed banded ironstone, with varying proportions of haematite and magnetite. Magnetite ore with a relatively high manganese content of about 5% Mn3O4 is exposed on the south bank of the Thukela opposite the site of Wosi [41]. Ore from the more distant Mamba source is a titaniferous magnetite with about 7% TiO2 [40]. The two Ndondondwane ores analyzed chemically (NDO22 and NDO34) had low titanium and relatively high manganese contents, and closely match the values reported for Wozi ore [41]. Our analyses did not reveal the presence of vanadium, reported without analytical data by Loubser [23], in either Ndondondwane ores or slag. As a result, the Ndondondwane

material probably did not come from the vanadiferous magnetite outcrops near the site of Mamba.

6. Spatial distribution of metal working remains 6.1. Method of spatial analysis After confirmation of the visually based classification by the archaeometallurgical analyses, all 11 classes of material were plotted on maps of the site using a contour drawing program, SURFER 6.0. The masses (i.e. weight in grams) of artefacts in each class per occupational horizon were summed and these totals plotted in the

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10 8 6 4

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Fig. 13. Contoured plot of raw ore in the Upper Cultural Horizon at Ndondondwane (scale represents total mass in grams).

centre points of the relevant excavation and surface collection units (Fig. 2). Nine of the resulting plots are shown for illustration (Figs. 8e16). When these patterns are plotted by cultural horizons, the distinct temporal and spatial distributions are startling. 6.2. Results of spatial analysis When all remains are plotted as if the site were a single occupation (as originally reported by previous excavators), then it appears as if each stage of metal production is present simultaneously on the site. But when the distribution of remains is broken down by the occupational horizons described above, it appears that

the locus of metal producing activities shifted over time. In the Lower Cultural Horizon, all metal working remains were concentrated in two areas: a suspected forge in the Dung Area, and a somewhat less certain forge associated with the burnt hut floor 50 m to the south-west (Fig. 8). In the Middle Cultural Horizon, the main focus of metallurgical activity shifted to Midden 1 in the east, with some metal remains found in the Dung Area and the area between the Dung and Mound areas (Fig. 9). Very small quantities were found in Midden 3 at the north end of the site. In the Upper Cultural Horizon, two clusters were apparent, only one of which is displayed on the map. All of the archaeologically significant metallurgical remains in the Upper Cultural

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140 Midden 1

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Transect 1 - A single (NDOS50) sandy forge base, doubtful provenance.

80 70 60 50

-100.00 40 30 20

-150.00 10

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Fig. 14. Contoured plot of forge bases in the Middle Cultural Horizon at Ndondondwane (scale represents total mass in grams).

Horizon and associated deposits derive from the Mound Area (Fig. 10). The second cluster, not displayed, is the result of the field clearing activities of modern farmers and their accumulation of large pieces of slag at the southern edge of the site. A more detailed breakdown per category of metal working remains is even more revealing. In the Lower Cultural Horizon, raw ore (implying ore preparation) was found in the vicinity of two burnt hut floors, one near the Mound Area and one near the Dung Area, as well as in the suspected forging area on the northern side of the Dung Area (Fig. 11). In the Middle Cultural Horizon, in contrast, raw ore was associated clearly with Middens 1 and 3 in the peripheral arc (Fig. 12), implying ore preparation in or near domestic areas. Raw ore was

found in the Upper Cultural Horizon only in direct proximity to the smelting furnaces and slag pits in the Mound Area (Fig. 13). Only one somewhat doubtful forge base was found in the Lower Cultural Horizon in the Dung Area. In the Middle Cultural Horizon, forge bases were concentrated strongly in Midden 1 (Fig. 14). Tellingly, Midden 1 was also the major concentration of indeterminate slag for this horizon (Fig. 15). No forge bases were found in the Upper Cultural Horizon, implying the absence of this activity during the final phase at the site. The distribution of indeterminate slag confirms these observations in that it clustered in and around the find-spots of the forge bases, in addition to the suspected forges in the Dung Area.

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50.00

90 85 80 75 70 65

0.00 Transect 1 probably intrusive from horizon 3

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45 40 35 30

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Fig. 15. Contoured plot of indeterminate slag in the Middle Cultural Horizon at Ndondondwane (scale represents total mass in grams).

Smelting slag (or massive slag) was only found in the Upper Cultural Horizon (Fig. 16), in direct association with the raw ore from this horizon (compare with Fig. 13). All metal working activity during this phase of occupation was concentrated in the Mound Area where the furnace bowl and slag dump were located [23]. The concentration of smelting slag in the dump north of the furnace (Fig. 16) would be far more marked if the ca. 500 kg of slag reported by Loubser [23] were included in the plot, which it is not. Most of the metal fragments also came from this area, including a small copper bead and a rolled iron cylinder [26], and four iron rings and three short sections of copper wire [23], all not included in the assemblage studied.

Temporally, the distribution of metal remains can be summarized as follows: metal remains are found in each cultural horizon, but the stages of metal production are not coeval within the site nor are they spatially continuous. It is clear that there is evidence of raw ore processing in each of the cultural horizons. However, it does not necessarily mean that all stages of production are present in each horizon. In fact, all of the subsequent stages of metal production are not so clearly represented in each horizon. In the Lower Cultural Horizon, raw ore storage and forging activities are present and focused on the Dung and Burned House Areas. In the Middle Cultural Horizon, the same activities are repeated, but their spatial distribution shifts to the Dung Area, plus

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80 Mound Areafurnace, slag pits, and +-300-500 kgs of slag

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30 20

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Fig. 16. Contoured plot of smelting slag in the Upper Cultural Horizon at Ndondondwane (scale represents total mass in grams).

peripheral Domestic Middens 1 and 2. In the Upper Cultural Horizon, charcoal preparation and smelting activities take place in the Central Area.

7. Discussion and implication of spatial distributions The spatial distribution of iron working remains at Ndondondwane has implications for social organization in the EIA. It has been argued that there was a significant difference in the organization of smelting between the EIA and LIA in South Africa [34,48], although this is not a consensus belief [18e20]. In EIA contexts, evidence for smelting (based upon the presence

of furnace fragments) has been claimed from the centre of several sites, including Magogo [29], KwaGandaganda [34], Mamba, Wosi [40,41], and Ndondondwane [23], but only the latter had in situ remains of a furnace. Almost of the sites, with the exception of Ndondondwane, are multi-period EIA occupations or multiple occupations within a single period. Most are analyzed as if all of the features of the same ceramic period were contemporary. As a result, it is commonly assumed that the presence of a furnace (or fragments) in the centre of a site indicates it is contemporary with the rest of the occupational debris. Owing to the nature of excavation and the low micro-chronological resolution of most studies, it is impossible to determine if the furnaces

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date from the actual residential occupations or from immediate post-occupational activities. Only at Ndondondwane has it been possible to distinguish between micro-phases within the Ndondondwane ceramic tradition, allowing the relationship between smelting and occupation to be elucidated. During the LIA, in contrast, furnaces appear to be located outside settlements, in accordance with the ethnohistoric and ethnographic literature that records smelting as something men do in ritual seclusion. This apparent difference in the location of smelting activities between the EIA and LIA has been used to argue that there is little cultural continuity between the two periods [34,39,48]. The current analysis of the Ndondondwane data casts doubt on this distinction. Three phases of deposits have been identified at the site. The first two, the Lower and Middle Cultural Horizons, date to the occupation of the site. The last, Upper Cultural Horizon, is an abandonment horizon during which there is no evidence for domestic activities at the site. Given the current understanding of site layout, the spatial and temporal distribution of smelting and forging operations suggests a revision of our understanding of EIA spatial organization. Forging was found in each of the occupation horizons, often associated with domestic activity areas. It was conducted in open and visible locations. Raw ore was found associated with domestic activity areas in the Lower and Middle Cultural Horizons. The presence of raw ore in domestic areas is obviously not a predictor of smelting operations, but speaks of the role of families in the collection, grading, and/or storage of raw ore prior to smelting operations. Smelting and charcoal preparation were not evident anywhere in the site until the Upper Cultural Horizon, and earlier than this smelting must have taken place elsewhere, i.e. outside the domestic precinct. The Lower and Middle Cultural Horizons also contain evidence of secondary metal working in the form of forging related activities. Concentrations of indeterminate slag and forge bases were found in association with domestic areas in the periphery and with the livestock enclosure in the centre of the site. In these horizons, no clear evidence of metal working was found with the ivory workshop, men’s gathering area, and presumed ritual precinct at the centre of the site. Secondary metal working was clearly not done in seclusion and was located in domestic areas, as in the LIA. The only concrete evidence for smelting at the site comes from the Mound Area in the final stratigraphic horizon, the Upper Cultural Horizon. This clearly was not a domestic occupation horizon. The central furnace was built and used during a phase when nobody appears to have been living at the site. The Charcoal Preparation Area at the southern end of the site is contemporary with this feature. Given the current interpretation of the stratigraphic sequence, it would appear that the spatial

organization of iron smelting at Ndondondwane was not significantly different from that of the LIA, that is, away from the occupation areas and hidden from the view of prying eyes. The location of the furnaces in the Mound Area after termination of the domestic occupation of the site suggests much more cultural continuity in iron smelting and processing between the EIA and LIA than suspected from earlier studies of this site. It is significant that the choice of the area for construction of the furnaces was in the central men’s area, with perceived special prior significance. It has been argued that since the Mound Area is where the clay mask fragments were found, this is where social transformation rituals are likely to have taken place during the main occupation of the site [23]. Thus, the Mound Area was associated with activities of transformation, and immediately subsequent smelters ( possibly resident across the river at Wosi) may have made a conscious choice to build their furnace in the Mound Area at Ndondondwane for this reason. At any rate, during the main occupation of the site (Middle Cultural Horizon), smelting must have been done away from the domestic area, outside the perimeter of the residential precinct.

8. Conclusions Consideration of the spatial, temporal, petrographic, and metallographic analyses allows the following conclusions to be drawn. Remains of primary iron smelting, and secondary forging activities are present on the site, although these appear to be separated temporally. In the earliest of three identified occupational horizons relatively sparse metal working remains were associated with forging activities near hut floors in the centre of the site. In the intermediate occupational horizon metal working on the site was confined to ore preparation and forging in the vicinity of the more peripheral domestic areas associated with middens. Any smelting must have been performed elsewhere. In the final occupational horizon metal working was concentrated in the central area again, where the remains of a furnace and a dump containing about 500 kg of slag attest to primary iron smelting. Smelting slag was characterized by the inclusion of unreacted lumps of ore and pseudomorphs of embedded charcoal. Some smaller slag nodules, showing more fluid structures and consisting predominantly of fayalite and wu¨stite, may have been either forging or smelting slag. The distinction between smelting and forging often is not possible on the basis of slag analysis alone, because they grade into each other and smelting slag can be discarded in forging localities with the cleaning of the bloom. At Ndondondwane, the location of distinctive structures like the smelting furnace, as well as the identification of characteristically shaped forge


bases, enabled the distinction of specific metal working activity areas to be made. Only iron production was carried out, and there is no evidence for production or working of copper. The iron ore used was metamorphosed banded ironstone, probably originating from outcrops, such as the one at Wozi, within the Tugela terrane. Inclusion of minerals derived from the distinctive local country rock, the Wozi amphibolite, showed that local clays were used for the construction of furnaces and tuyeres. Sand derived from the amphibolite was added to the furnace charge as a flux, to assist in reducing the high grade iron ores. The furnace conditions did not reach equilibrium, with more refractory ore nodules remaining only partially reduced, and included in the slag waste. The iron objects recovered from the site were extremely corroded. Few EIA items survived the corrosive soils, and none of these were sufficiently well preserved to allow the identification of their original shape or function. The residual metal showed the characteristic banding of bloomery iron, with layers of differing carbon content derived from heterogeneities in the original bloom, strings of elongated two-phase inclusions consisting of globules of the iron oxide wu¨stite in glass, and the occasional weld which trapped surface scale as complex oxide inclusions. The carbon content ranged from nearly pure ferrite to patches of up to 0.7%C. The largest object, the pointed fragment of a probable hoe shank, also contained some patches of martensite. Martensite is conventionally associated with quenching, but in this case was probably due to the locally high carbon content promoting martensite formation at moderate cooling rates. The grain size and shape in these metals indicated both hot and cold working, with air cooling from temperatures in the region of 900 (C. These metal fragments did not differ in any significant way from those recovered from other southern African EIA sites, such as KwaGandaganda [33,34] and Broederstroom [32] in South Africa, and Divuyu and Nqoma in Botswana [33]. The analysis of the metal finds from Ndondondwane informs us as to the nature of metal working activities in an EIA village. Forging occurred in open and visible locations, and in and around domestic zones. Contrary to previously held views, smelting at Ndondondwane took place outside the residential village, and in the central area only after domestic abandonment. This evidence suggests more substantial cultural continuity in social organization of metal production from the EIA to the LIA than generally believed, and necessitates a revision of earlier interpretations of the significance of the spatial relations of EIA remains at Ndondondwane. The results presented here challenge archaeologists concerned with Iron Age settlements to begin to attempt to achieve the level of internal chronological control

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necessary for monitoring such changes. Rather than assuming that all features were contemporary within a period, it is necessary to control for sub-period or phasing of activities at a settlement. Only then can accurate assessments of the nature of activities be made.

Acknowledgements We would like to thank Amafa aKwaZulu-Natali for access to the material, David Reid (Department of Geological Sciences, UCT) for the XRF analyses, and Avinash Bisnath for copies of geological maps. Financial support from the University of Manitoba (UM/ SSHRC), Social Science Research Foundation of Canada, Anglo-American Chairman’s Fund Educational Trust, De Beers Educational Trust, the University of Cape Town Research Committee, and the South African National Research Foundation is acknowledged. Tina L. Jongsma, Len O. van Schalkwyk, Gavin Whitelaw, Kent Fowler, and the reviewers (anonymous and otherwise) have all contributed to the development of the analysis and thoughts expressed in this paper and their contributions are greatly appreciated. Matthew Singer helped with the reorganization of the data so that it could be expressed in a digital spatial analysis. Thanks must also be extended to Len van Schalkwyk for allowing the use of his map for Fig. 1. Opinions expressed in this paper and conclusions arrived at are those of the authors and are not necessarily to be attributed to any of the supporting agencies. References [1] A. Bisnath, Geology of the Tugela group rocks in the Nsuze River valley, Tugela Terrane, Natal Belt, South Africa, MSc, University of Durban, Westville, South Africa, 2000. [2] J.R. Denbow, Cows and Kings: a spatial and economic analysis of a hierarchical Early Iron Age settlement system in Eastern Botswana, in: M. Hall, G. Avery, D.M. Avery, M.L. Wilson, A.J.B. Humphreys (Eds.), Frontiers: Southern African Archaeology Today, British Archaeological Reports, International Series, BAR, Oxford, 1984, pp. 24e39. [3] J.R. Denbow, A new look at the later prehistory of the Kalahari, Journal of African History 27 (1986) 3e28. [4] T.M. Evers, W.D. Hammond-Tooke, The emergence of South African chiefdoms: an archaeological perspective, Journal of African Studies 45 (1986) 37e42. [5] K.D. Fowler, Early Iron Age community organization in southern Africa: social and symbolic dimensions of ceramic production, use and discard at Ndondondwane, PhD Thesis, University of Alberta, 2002. [6] M. Godelier, Rationality and Irrationality in Economics, New Left Books, London, 1972. [7] H.J. Greenfield, Aspects of recent research at Ndondondwane: a response to Loubser, South African Field Archaeology 6 (1998) 61e79. [8] H.J. Greenfield, L.O. Van Schalkwyk, Spatial models of intrasettlement spatial organization in the EIA of southern Africa:

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[9]

[10]

[11]

[12]

[13]

[14]

[15]

[16]

[17] [18] [19] [20] [21]

[22] [23]

[24]

[25]

[26]

[27]

[28]


a view of Ndondondwane on the central cattle pattern, in: C. Cluny (Ed.), An Odyssey of Space (Paper Presented at the 2001 Chacmool Conferences), Archaeological Association of the University of Calgary, Calgary, 2001. H.J. Greenfield, L.O. Van Schalkwyk, Intra-settlement social and economic organization of Early Iron Age farming communities in southern Africa: view from Ndondondwane, Azania 28 (2003) 121e137. H.J. Greenfield, L.O. Van Schalkwyk, T.L. Jongsma, Ndondondwane: preliminary report on the 1995 survey and excavations, Nyame Akuma (Journal of the Society for Africanist Archaeologists) 47 (1997) 42e52. H.J. Greenfield, L.O. Van Schalkwyk, T.L. Jongsma, Surface and subsurface reconnaissance at Ndondondwane: preliminary results of the 1995e97 field seasons, Southern African Field Archaeology 9 (2000) 5e15. M. Hall, Settlement patterns in the Iron Age of Zululand: An Ecological Interpretation, British Archaeological Reports, International Series, BAR, Oxford, 1981. M. Hall, Archaeology and modes of production in pre-colonial southern Africa, Journal of Southern African Studies 14 (1987) 1e17. E.C.I. Hammerbeck, G.P. Fourie, A.A. Snyman, J.J. Schoeman, Iron, in: C.B. Coetzee (Ed.), Mineral Resources of the Republic of South Africa, Government Printer, Pretoria, 1976, pp. 147e158. T.N. Huffman, Archaeology and ethnohistory of the African Iron Age, Annual Review of Anthropology 11 (1982) 133e150. T.N. Huffman, Iron Age settlement patterns and the origins of class distinction in southern Africa, Advances in World Archaeology 5 (1986) 291e338. T.N. Huffman, Iron Age Migrations, African Studies Monograph Series, University of Witwatersrand, Johannesburg, 1989. T.N. Huffman, Broederstroom, and the origins of cattle keeping in southern Africa, African Studies 49 (1990) 1e12. T.N. Huffman, Broederstroom and the Central Cattle Pattern, South African Journal of Science 89 (1993) 220e226. T.N. Huffman, The Central Cattle Pattern and interpreting the past, Southern African Humanities 13 (2001) 19e35. R. Klein, The prehistory of Stone Age herders in South Africa, in: M. Hall, A.B. Smith (Eds.), Prehistoric Pastoralism in Southern Africa, South African Archaeological Society, Vlaeberg, 1986, pp. 5e12. A. Kuper, Wives for Cattle: Bridewealth and Marriage in Southern Africa, Routledge and Kegan Paul, London, 1982. H. Loubser, Ndondondwane: the significance of features and finds from a ninth century site on the lower Thukela River; Natal, Natal Museum Journal of Humanities 5 (1993) 109e151. T.O. Maggs, Msuluzi confluence: a seventh century Early Iron Age site on the Tugela River, Annals of the Natal Journal of Humanities 26 (1980) 111e145. T.O. Maggs, Iron Age settlement and subsistence patterns in the Tugela River Basin, Natal, in: M. Hall, G. Avery, D.M. Avery, M.L. Wilson, A.J.B. Humphreys (Eds.), Frontiers of Southern African Archaeology Today, British Archaeological Reports, International Series 207 (Cambridge Monographs in African Archaeology; no. 10), BAR, Oxford, 1984, pp. 194e206. T.O. Maggs, Ndondondwane; a preliminary report on an Early Iron Age site on the lower Tugela River, Annals of the Natal Museum 26 (1984) 71e94. T.O. Maggs, The Iron Age south of the Zambezi, in: R. Klein (Ed.), Southern African Prehistory and Paleoenvironments, Balken, Rotterdam, 1984, pp. 329e360. T.O. Maggs, M. Michael, Ntshekane: an Early Iron Age site in the Tugela Basin, Natal, Annals of the Natal Museum 22 (1976) 705e740.

[29] T.O. Maggs, V. Ward, Early Iron Age sites in the Muden area of Natal, Annals of the Natal Museum 26 (1984) 95e138. [30] P.E. Matthews, E.G. Charlesworth, A geological review of the northern margin of the Proterozoic Namaqua-Natal mobile belt in Natal, Geocongress ’81, Guidebook, Geological Society of South Africa, Johannesburg, 1981. [31] D.E. Miller, The Tsodilo Jewellery e Metal Work from Northwestern Botswana, University of Cape Town Press, Cape Town, 1996. [32] D.E. Miller, Smelter and smith: metal fabrication technology in the southern African Early and Late Iron Age, Journal of Archaeological Science 29 (2002) 1083e1131. [33] D.E. Miller, N.J. van der Merwe, Early Iron Age metal working at the Tsodilo Hills, northwestern Botswana, Journal of Archaeological Science 21 (1994) 101e115. [34] D.E. Miller, G. Whitelaw, Early Iron Age metal working from the site of KwaGandaganda, Natal, South Africa, South African Archaeological Bulletin 49 (1994) 79e89. [35] D.W. Phillipson, African Archaeology, Cambridge University Press, Cambridge, 1985. [36] M. Sahlins, Stone Age Economics, Aldine, Chicago (IL), 1972. [37] L.E. Samuels, Optical Microscopy of Carbon Steels, American Society for Metals, Metals Park (OH), 1980. [38] E. Terray, Marxism and Primitive Society, Monthly Review Press, New York, 1972. [39] L.O. Van Schalkwyk, Society in transformation: Early Iron Age mixed-farming communities in the Lower Thukela Basin, Zululand, MA, Department of Archaeology, University of Cape Town, 1992. [40] L.O. Van Schalkwyk, Mamba confluence e a preliminary report on an Early Iron Age industrial centre in the lower Thukela Basin, Zululand, Natal Museum Journal of Humanities 6 (1994) 119e152. [41] L.O. Van Schalkwyk, Wosi, an Early Iron Age agriculturist village in the lower Thukela Basin, Zululand, Natal Museum Journal of Humanities 6 (1994) 65e117. [42] L.O. Van Schalkwyk, Settlement shifts and socio-economic transformations in early farming communities in the lower Thukela basin, Zululand: a revisionist model, Azania 29e30 (1996) 187e198. [43] L.O. Van Schalkwyk, H.J. Greenfield, T.L. Jongsma, Ndondondwane: preliminary report on the 1995 survey and excavations, Southern African Field Archaeology 6 (1997) 61e79. [44] L.O. Van Schalkwyk, R.J. Rawlinson, The archaeological excavations of Ondini, the Royal Capital of King Cetshwayo ka Mpande: 1873e1879, in: P.G. Stone, P. Plane (Eds.), The Constructed Past: Experimental Archaeology, Education and the Public, One World Archaeology Series, UNESCO, Routledge, London, 1999, pp. 269e281. [45] E.A. Voigt, The dispersion of domestic stock into southern Africa, Archaeozoologia Melanges (1987) 149e159. [46] E.J. Watson, V. Watson, ‘Of commoners and kings’: faunal remains from Ondini, South African Archaeological Bulletin 45 (1990) 33e46. [47] G. Whitelaw, Customs and settlement patterns in the first millennium AD: evidence from Nanda, an Early Iron Age site in the Mngeni Valley, Natal, Natal Museum Journal of Humanities 5 (1993) 47e81. [48] G. Whitelaw, KwaGandaganda: settlement patterns in the Natal Early Iron Age, Natal Museum Journal of Humanities 6 (1994) 1e64. [49] G. Whitelaw, Southern African Iron Age, in: J.O. Vogel (Ed.), Encyclopedia of Precolonial Africa, Altamira Press, Walnut Creek (CA), 1997, pp. 444e456. [50] G. Whitelaw, M. Moon, The ceramics and distribution of pioneer agriculturalists in KwaZulu-Natal, Natal Museum Journal of Humanities 8 (1996) 53e79.