Experimental characterisation of microscopic hafting traces and its application to archaeological...

Veerle Rots and Pierre M. Vermeersch156

Veerle Rots and Pierre M. Vermeersch

18. Experimental characterization of hafting tracesand their recognition in archaeological assemblages

IntroductionIn the past, the concept of hafting has only been describedin rather general terms. Keeley (1982) is one of the few tohave devoted attention to the subject and to have pointedat the importance of hafting for correctly interpreting thearchaeological record. Nevertheless, traces that werepotentially related to hafting were observed frequently(e.g. Keeley 1980; Vaughan 1985), but due to a lack ofreference material, they were rarely interpreted as such.Practically no hafting experiments were undertaken on asystematic basis. On some occasions, hafted tools wereproduced for use-wear experiments, but the resultinghafting traces were hardly ever investigated (e.g. Kam-minga 1982). Only a few analysts have really attemptedto characterize hafting traces (Odell and Odell-Vereecken1980; Odell 1980; 1981; Plisson 1982; Moss and New-comer 1982). The first breakthrough in hafting researchwas the conference organized by D. Stordeur in 1984(Stordeur 1987). For the first time a group of analysts sattogether to discuss the problem of hafting. The conferencealso led to the undertaking of some specific haftingexperiments and the analysis of the hafting tracesproduced. Nevertheless, investigations remained limitedand unsystematic in nature and often lacked a soundexperimental basis.

In this paper, we present data regarding hafting tracesand some of the factors influencing their production. Manyfactors can be proposed, as for instance the specifichafting arrangement used – including haft type, haftmaterial and fixation method – worked material, action

undertaken and use duration. Here, we will focus on theinfluence of action and worked material, starting withtools used for adzing wood, for which many archaeo-logical examples exist and which we will compare withadzing earth and scraping wood.

First, we examine whether the characteristics of haftingtraces differ from those of use-wear traces. Second, weinvestigate in what way action and worked materialinfluence the production of hafting traces. Third, weinvestigate some archaeological examples of adze-scrapers used for adzing wood for hafting traces from theEarly Neolithic site of Vaux-et-Borset, Belgium (Casparet al. 1993; Rots 2002a).

Methodology

ExperimentsAll experiments were conducted in collaboration with theChercheurs de la Wallonie of the Prehistoric Museum ofRamioul (Liège, Belgium). All lithic tools were manufac-tured in a fine-grained flint. All of the experimentsconcerned a juxtaposed haft-type, with the tool placeddistally in a transverse direction with the active partoriented perpendicularly. Further details concerning theexperiments are included in Table 18.1. The descriptionof the hafting arrangement is based on the terminologyproposed by Stordeur (1987, 23).

In order to allow an easy comparison between thedifferent tools, this paper only concerns experimental

Microscopic functional research has mainly been concentrated on use-wear traces visible on workingedges. The rest of the tool was largely neglected, although other parts can just as well bear traces worthexploring. Not only technological traces, resulting from production, but also prehension or hafting tracescan be observed. The latter traces have never been the object of a systematic study. We present data relatedto the influence of action and worked material on the production of hafting traces. Our approach is mainlyexperimental, but we also include some archaeological examples of traces that duplicate the distinctiveexperimental data.

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Getypte tekst

E.A. Walker, F. Wenban-Smith and F. Healy (eds) 2004. Lithics in Action: Papers from the Conference Lithic Studies in the Year 2000, Oxford: Oxbow books: 156:168.

Experimental characterization of hafting traces 157

tools mounted on a juxtaposed haft and fixed withbindings (Figure 18.1). Wood and antler were used ashaft materials; bindings were made out of wet leather,dry leather or lime bast – when leather bindings areapplied in wet condition and then left to dry, they producea much better fixing than standard leather bindings. In afew cases the tool was wrapped in a piece of leather beforeit was mounted on the haft, to protect the bindings frombeing cut. In the case of wood adzing, the scraper washafted with its dorsal face against the haft; in the case ofearth adzing, the ventral face made contact; and in thecase of wood scraping, both arrangements were tried.

Equipment and artefact preparationA stereoscopic microscope (Wild M5–22827, magnifi-cations 6x–100x) was used to investigate tool damage,according to the principles set out by Tringham et al.(1974) and further elaborated by Odell (1977). Tools werefurther analysed with a metallurgical microscope (Olym-pus BX60M MDPlan 10, MSPlan 20, MSPlan 50), usingbright field illumination as described by Keeley (1980).

For the latter type of analysis, all experimental tools werecleaned for a short period in 10% hydrochloric acidsolution to remove adhering residues. During the analysis,tools were cleaned with acetone.

TerminologySince the area near the haft limit is important andsometimes carries traces different from those on the restof the hafted part, we divided each tool into three parts:the proximal hafted part, the medial part (correspondingwith the zone around the haft limit) and the distal, unhaftedpart (Figure 18.2).

AnalysisDetails concerning the lithic tools used are included inTable 18.2. The most diagnostic hafting traces werepolishes, scarring and bright spots. Striations were notvery numerous, but they occasionally marked the limit ofthe haft. Rounding of edges and ridges, and smoothing ofsurfaces is usually very limited and non-diagnostic in this

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Exp. 1 Direct Wood Leather bindings 0 Dorsal Proximal part Adzing 0.30.30 0 Wood Scraper



Exp. 4 Indirect Wood Leather bindings 1 Dorsal Proximal part Adzing 0.20.14 0 Wood Scraper

Exp. 5 Indirect Wood Leather bindings 1 Dorsal Proximal part Adzing 0.39.25 0 Wood Scraper

Exp. 6 Direct Antler Vegetal bindings 0 Dorsal Proximal part Adzing 0.36.32 0 Wood Scraper

Exp. 7 Indirect Wood Dried leather bindings 1 Dorsal Proximal part Adzing 0.30.09 0 Wood Scraper

Exp. 8 Direct Antler Vegetal bindings 0 Dorsal Distal part Adzing 0.02.11 1 Wood Scraper

Exp. 9 Indirect Wood Vegetal bindings 1 Dorsal Proximal part Adzing 0.14.34 1 Wood Scraper

Exp. 10 Direct Wood Leather bindings 0 Ventral Proximal part Adzing 1.00.00 0 Earth Scraper

Exp. 11 Direct Antler Leather bindings 0 Ventral Proximal part Adzing 1.00.00 0 Earth Blade

Exp. 12 Direct Wood Vegetal bindings 0 Ventral Proximal part Adzing 4.00.00 0 Earth Scraper

Exp. 13 Direct Wood Leather bindings 0 Dorsal Proximal part Scraping 0.30.00 1 Wood Scraper

Exp. 14 Direct Antler Vegetal bindings 0 Ventral Proximal part Scraping 0.30.00 0 Wood Scraper

Exp. 15 Indirect Wood Dried leather bindings 1 Ventral Proximal part Scraping 0.30.34 0 Wood Scraper

Exp. 16 Direct Wood Vegetal bindings 0 Dorsal Proximal part Scraping 0.31.22 0 Wood Scraper

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Table 18.1 Experimental details (0 = absent; 1 = present).

Figure 18.1 Juxtaposed hafting with leather bindings. Figure 18.2 Tool terminology and hafting limit.


set of experiments. Specific trace characteristics aredescribed, including intensity, morphology, distributionand pattern.

Adzing woodSufficiently developed hafting traces were produced onthe hafted part of both the dorsal and the ventral contactsurfaces after a use of about 14 minutes. Well-developedtraces required a use of about 20 minutes. The longestuse duration in this set of tools was 40 minutes.

The experimental traces were compared with the onesobserved on archaeological tools. One important remarkneeds to be made. The hafting traces visible on the adze-scrapers of Vaux-et-Borset, show that these tools weremost likely hafted by the aid of leather bindings withtheir ventral face against a juxtaposed wooden haft (Rots2002a). The morphology of our experimental tools didnot allow such a hafting mode. Their working anglecombined with their straight longitudinal section requireddorsal haft contact to ensure efficient tool use. Traces arenot as easily produced on ventral as on dorsal faces, dueto the irregular morphology of the latter. When comparingthe resulting hafting traces, we had, therefore, to payattention to this difference in hafting mode.

PolishWood and antler. The dorsal face carried the best-developed polish, while polish on the ventral face washardly visible. When a wrapping was used, polish wasequally developed on both faces, but less developedoverall. The best-developed polishes were observed onthe ridges between dorsal flake scars (Figure 18.3), whichall had a direct or indirect contact with the wooden orantler haft. Edges showed far less polish while surfaces

usually showed a kind of general polishing, but no realidentifiable polish. In the medial zone, polish was mostextensive and interpretable (Figure 18.4). Extensivedamage on the butt prevented extensive polish formationin the proximal zone.

Wood and antler hafting polishes are not very differentin morphology from their respective use polishes. Thedistinction between them is thus based on the samemorphological grounds (Keeley 1980). There were,however, differences in the distribution of use and haftingpolishes. While use polishes are best developed on theouter edges and then gradually extend towards the innersurface, hafting polishes tend to follow the tool’s micro-topography towards the inner surface, without reallyhaving an impact on the outer edge or ridge. Since thehaft material is hard, polish development is better on theouter ridges without really intruding in the lower surface

Exp. Id Dorsal transversal Butt protrusion

curvature

Exp. 1 Trapeze Dorsal

Exp. 2 Triangle Dorsal

Exp. 3 Sub-triangle Dorsal


Exp. 5 Convex Dorsal



Exp. 8 Sub-triangle Ventral


Exp. 10 Sub-triangle Ventral


Exp. 12 Convex None


Exp. 14 Trapeze Dorsal

Exp. 15 Triangle None


Table 18.2 Lithic tool details.

Figure 18.3 Wood hafting polish on medial ridge (exper-imental tool 1).

Figure 18.4 Antler hafting polish on dorsal medial surface(experimental tool 6).


zones. Polish is usually continuously distributed, but whena wrapping is used, it is discontinuous in the medial zone.

Due to their different hafting arrangement, haftingtraces could only be present on the ventral face of thearchaeological tools. Due to slow polish development onthis face, it is no surprise that they were found to be verylimited. However, there did seem to be sufficient data tostate the haft was made out of wood. Limited wood polishassociated with scarring was observed on some edges andon the ventral butt (Figure 18.5).

Leather binding. Contact with standard leather bind-ings – i.e. applied when dry – produced a rough polish,but brighter than expected (cf. Keeley 1980, 49). Withthe soft nature of bindings, polish was not limited to theedge, but was as developed towards the inner surface.This was also visible on the archaeological tools (Figure18.6). In the case of retouched edges, the scar ridgescarried the best-developed polish.

Wrapping. The polishes described above can easily bedistinguished from the one produced by a wrapping. Theuse of a wrapping makes hafting polishes less welldefined, which is best illustrated with the observations onthe dorsal face of experimental tools 4 and 5. These toolshad an indirect contact with wood and the polish producedis clearly a mixture of hide and wood characteristics(Figure 18.7). While the polish morphology resembleshide, both wood and hide influence its distribution. Onthe one hand, it is better developed in higher zones andon the other hand, it intrudes more into the inner surface.This should be no surprise, since the wrapping functionsas a second skin of the tool, polish produced in zonesmaking most contact with the wooden haft. Since awrapping also fills up space in between the surface andthe haft, the contact surface is enlarged. Second, awrapping reduces the amount of friction in a haft, due towhich polishes are generally less developed than in casesof direct contact.

Based on our observations, distinguishing indirectcontact should not be problematic. To our knowledge, awrapping is always made out of leather, implying arecurrent combination of a soft wrapping and a hard haft.Hide-like polish morphology associated with wood-likedistribution should leave no doubt concerning the indirectnature of the haft contact. Furthermore, leather bindingsproduce a somewhat brighter polish than would beexpected, while polish resulting from wrapping-use is dull.We did not observe any such traces on the archaeologicaltools.

Vegetal bindings. Only the hafting arrangement ofexperimental tool 6 included vegetal lime bast bindings,but an intermediate leather piece prevented direct contactwith these bindings. As such, we do not have data forcharacterizing the resulting traces.

Figure 18.5 Wood hafting polish on ventral butt (VBT8989C 0–10).

Figure 18.6 Polish of leather bindings on ventral medialedge (VBT89 89D 0–10).

Figure 18.7 Indirect contact with wooden haft (wrapping)on proximal ridge (experimental tool 5).


Polish: summaryBased on this first set of experiments, a general toolcharacteristic can be pointed out which influences theproduction process of hafting traces. A tool’s transverseconvexity is a very important factor in the case of haftingagainst a medium to hard material, i.e. the geometric figureformed in cross-section, as for instance a triangle in thecase of one central ridge or a trapeze in the case of twomain ridges (Table 18.2). If the dorsal ridges protrudemuch above the dorsal surface (as in experimental tool1), they will enter into the haft material (as in the case ofwood) and bear well-developed hafting traces. If thedorsal surface is convex in cross-section, as in experi-mental tool 5, we can observe a lower concentration onthe ridges and a better development of the surface polish.Hafting traces are spread over a larger part of the surface,but the general development is slightly lower.

ScarringScarring from hafting was often very extensive on toolsused to adze wood. It was mainly concentrated on the buttand consisted of crushing due to the fact that the tool wasforced against the haft. The protruding face of the butt –in these experiments this was the dorsal face – took most(or all) of the crushing, while the ventral side hardly show-ed any damage. Such extensive crushing on archaeologicaltools can, therefore, prove the use of a stopping ridge.

Edge damage was also often significant, includingscalar feather-terminating scars and in lesser amountshinge- and step-terminating scars (Ho Ho Committeeclassification, Hayden 1979, 133–135) in a run-togetherdistribution (terminology after Odell 1981). Damage waspresent all along the edge, but often slightly moreextensive near the haft limit and the butt. Ridge damagewas low and restricted to a crushing of limited portions.

Four factors had an important influence on the amountof scarring produced and need to be considered for acorrect interpretation of hafting traces. The first is whetherthe edge is retouched. Intentional retouch not only reducesthe amount of damage, it is also hard to distinguish fromhafting damage. This has also been noted for use damageby Keeley (1980, 25–28). Most experimental tools hadone or two retouched edges, unfortunately mainly dorsal.When the dorsal face is fixed against the haft, mostscarring will occur there, since the bindings put pressureon the ventral face. This was illustrated in experimentaltool 1, where the dorsal left and ventral right edgeremained unretouched. While the latter hardly shows anydamage, the former shows large feather- and step-terminating scalar scars. Occasionally, additional evi-dence can provide a link between scars on retouched edgesand hafting. Two zones on experimental tool 4 exemplifythis. The first zone is situated on the right haft limit,showing a small group of very intruding feather-termin-ating scars with small step-terminating scars at theirinitiation (almost crushing). At the initiation of retouchscars, a series of small scars can also frequently be

observed, but which do not have the more abrupt step-termination that we see in the hafted zone here. Althoughsimilar combinations can be observed in other zones moretowards the butt, this is the only case leaving no doubtabout its origin, due to its clear link with the haft limitand its intrusive nature which is impossible to produce byretouch. A second zone is situated on the most proximalleft edge, consisting of a series of intrusive hinge- andstep-terminating scalar and rectangular scars, with fewsmall abruptly terminating scarring at their initiation. Notonly are the scar characteristics for both these zonesevidence of hafting, but also their position in the areassubmitted to most pressure.

A second factor is the transversal convexity of a tool,this has an important influence on the amount of damageproduced and on the occurrence of fractures. A tool witha triangular cross-section is difficult to haft securely withits dorsal face against the haft, even if there is a slightgroove in the haft. The resulting hafting arrangement willnot be very secure and a space will remain in between thetool’s edges and haft. Furthermore, pressure is con-centrated on the single central ridge, instead of beingdistributed all over the surface. Such factors do not onlyenhance the likelihood of tool breakage (as happened inexperimental tool 2), they also lead to extensive edgedamage, since the pressure applied on the ventral edgesis not compensated by support of the haft. A good examplewas experimental tool 3, which showed extensive damageon its dorsal edges, with a clear limit corresponding withthe haft limit. The tool did not break in experimental tool4 thanks to its only having a partial triangular cross-section, limited to the medial zone, and the compensationof high edge angles and thickness. The archaeologicaltools studied were mostly sub-triangular or trapezoidal incross-section, which, combined with their high edgeangles, made them resistant to breakage.

A third factor is the use of a leather wrapping. Suchwrapping protects tool edges and reduces friction in thehaft, resulting in very limited scarring. This was illustratedby experimental tools 4 and 5. Since the dorsal edgeswere retouched, we were restricted to observing theventral edges on which only tiny feather-terminating scarscould be seen. The ventral edges of the other experimentaltools showed far more extensive and larger damage,including step-terminating scars.

The fourth and last factor is haft width in relation totool width. When a tool is wider than its haft, more edgescarring is produced, since more pressure is exerted onthe edges. When the haft is wider, it absorbs most of thispressure. In cases of dorsal haft contact, this factor is evenmore important, especially for triangular or sub-triangularcross-sections. In these cases, damage will be extensiveas soon as haft width is similar to tool width. A goodexample is experimental tool 3, whose medial width wasinitially over 30mm, as was the distal, but due to damage,was reduced to 27mm. The haft width was only slightlymore at 32mm, which meant that it did not absorb part of


the pressure applied on the tool’s edges. Consequently,damage in the medial zone was very vertical in nature.

On archaeological tools, a similar type of damage couldbe observed, but here the run-together patches were alsoalternating, pointing at a different binding method. Whilewe fixed tools on the haft by starting the bindings in themost distal part and then gradually turning one part of thebinding around the tool until the lithic tool was completelycovered, the differing damage on the archaeological toolssuggests a different method. Both parts of the bindingswere used at the same time, progressing from the haftlimit to the proximal part. Each time they arrived on topof the tool, they were crossed and turned back (Rots2002a). This is further confirmed by the fact that damageis as intense on the dorsal as on the ventral edges, implyingpressure was the same on both edges.

Bright spotsBright spots were shown to be one of the most importantaspects of hafting traces. They were often visible macro-scopically and generally occured in combination withscarring. Bright spots have always been considered asnot interpretable (e.g. Moss 1983, 81–82; Vaughan 1985,185–187) or as evidence of post-depositional alterations(Levi-Sala 1986, 231–232, 241). In several cases the lattermight be true. However, one should be very careful as totheir origin since our experiments provide indubitableevidence for a link with hafting (Rots 2002a; 2002b).Hafting bright spots are produced by intense friction of aflint particle detached in the haft with the lithic tool,explaining their close association with scarring. Thesespots are very bright, smooth and flat in nature (Figure18.8), often very large (up to several mm2) and dependingon their development they can be completely linked up(Figure 18.9). They are further characterized by anorganized distribution limited to the hafted area andconcentrated near the haft limit and in the butt region. If

we compare this pattern with post-depositional surfacealteration bright spots, important differences can beobserved. The latter are present all over the tool and arecharacterized by a random distribution. Although theymight be present in proximity to scarring, they are notreally associated with it.

We observed slightly more bright spots on the dorsalsurfaces, due to their higher amount of scarring. Due toheavy crushing in the butt region, many bright spots occurin this zone. They also occur on edges and ridges inassociation with scarring (Figure 18.10). On surfaces theyare more limited, apart from near the edges.

Contact with a hard material seemed to enhance brightspot production, probably since the amount of scarring ismore extensive. A good example is experimental tool 7,which was fixed with dried wet-leather bindings. Suchbindings are a lot harder than standard leather bindingsand produce a more secure hafting. Therefore, it shouldbe no surprise that bright spots were thick-set. Contactwith an antler haft produced two types of bright spots.The first is the one described above, the second is mostlikely caused by an antler particle. The spots are un-dulating in nature and strongly resemble a well-developedantler polish (Figure 18.11). We never observed them inexperiments with a wooden haft. This type of bright spothas also been attributed to post-depositional alterations,but our evidence strongly suggests a relationship withhafting, if we take the characteristics mentioned aboveinto consideration.

Tool breakage during use strongly augments theamount of bright spots. This can be illustrated withexperimental tool 2, which broke in two places. The distalpart broke off at the haft limit in an almost straight fracturewith a small feather on the ventral side of the distal part,but with a clear impact point at the dorsal side of thefracture. It is clear that the pressure producing this fracturewas exerted parallel to the tool’s axis, otherwise the

Figure 18.8 Hafting bright spot on ventral medial edge(experimental tool 7).

Figure 18.9 Hafting bright spot on proximal ridge (exper-imental tool 6).


fracture would have shown signs of more bending.Furthermore, the location of the impact point proves thefracture initiated from the wooden haft. A second breakoccurred in the haft and was only noticed during de-hafting. The latter was combined with extensive damage,producing much friction in the haft and numerous brightspots. In this case, the bright spot distribution could beused (in combination with damage) to infer that the dorsalface of the medial part slid over the ventral face of theproximal part. Along with extensive damage (mostly largerectangular feather- and step-terminating scars withsubsequent crushing), these two zones are almost com-pletely covered with the typical hafting bright spots, whilethe zones on the opposite surface hardly show any.

Archaeological examples of similar bright spots arefrequently present, suggesting hafting. Like the ex-perimental ones, they often occur near likely haft limits,

on edges, surfaces and to a lesser degree on ridges.Furthermore, they are virtually always associated withedge damage. All stages of development were observed,ranging from those limited to the higher parts of themicrotopography (Figure 18.12) to the ones completelylinked up.

StriationsThe amount of striations largely depended upon thescarring intensity. Striations on or near edges (Figure18.13), on ridges (Figure 18.14) and on surfaces wereusually straight, smooth and abrasive in nature. They areproduced by the same process as bright spots – a detachedflint particle stuck in between tool and haft. Their closeassociation with bright spots (Figure 18.15) and the factthey sometimes consist of a linear series of bright spots(Figure 18.16) further confirms this. They are prefer-

Figure 18.10 Hafting bright spot associated with scarringon proximal ridge (experimental tool 1).

Figure 18.11 Hafting bright spot (antler) on dorsal proximalsurface (experimental tool 6).

Figure 18.12 Hafting bright spot on ventral proximal edge(VBT89 89C 0–10).

Figure 18.13 Hafting striation on ventral proximal edge(experimental tool 6).


Figure 18.14 Hafting striation on dorsal medial ridge(experimental tool 9).

Figure 18.15 Hafting bright spot with striation on ventralproximal surface (experimental tool 7).

Figure 18.16 Hafting bright spot in striation on ventralmedial surface (experimental tool 7).

Figure 18.17 Hafting striations on proximal ridge (exper-imental tool 6).

entially orientated parallel to the use motion. On the dorsalsurface of experimental tool 8, abrasive striations wereobserved on the exact haft limit, transversely across theaxis of use motion. The latter are in clear association withhafting edge damage. The proximal ridge of experimentaltool 6 showed a type of striation only observed in casesof direct contact against antler. It consisted of a polishedzone with numerous grooves with random orientation(Figure 18.17). Similar traces were observed by Kay andSolecki (2000, e.g. Figs. 5b, 6b, 9d, 9f). Our observationsconfirm their attribution to hafting and further suggestdirect hafting in antler. Dorsal surfaces also show straightstriations parallel to the use motion, but additive in nature.These seem to be due to an intense friction against thewooden haft.

On the archaeological tools, smooth abrasive striationscould be observed on their edges and surfaces, as well as

a linear series of bright spots. While some striations wereorientated parallel, most of them were oblique to thepresumed working axis. They are furthermore in closeassociation with edge scarring (Figure 18.18) and areregularly found with polish and bright spots.

Rounding and smoothingEdge rounding or surface smoothing was very limited. Itconsisted of a very limited localized rounding of ridgesassociated with a more intense polish in zones with aslight change in ridge direction (experimental tools 1, 4,5), a limited edge rounding due to leather bindings(experimental tools 3, 4), or a light surface smoothing(experimental tool 5). On the archaeological tools, weobserved a limited rounding of medial, sometimesproximal, edges, associated with a leather polish.


Adzing earthThere was ample evidence that adzing wood produceswell-developed hafting traces. In order to investigate theimportance of worked material resistance for the pro-duction of hafting traces, these were compared with thoseproduced in the case of adzing earth, a low resistancematerial. Even without investigating the microscopictraces, it was obvious that tool impact was lower. Theworking edges were hardly damaged and remained usablefor a long period since efficient working angles wereretained. Tool breakage and heavy hafting damage didnot occur.

On a macroscopic level, working earth had one obviousadvantage. Working edges intruded far into the earth,producing extensive use traces clearly marking the haftlimit. Macro- and microscopic hafting traces on the otherhand, were far more limited. Polishes were only welldeveloped after extensive use, scarring was low and bright

spots were not frequent. Hardly any rounding wasproduced, apart from after very long use (experimentaltool 12), and striations were rare. Ventral haft contactonly partially accounts for this difference.

PolishPolish was generally best-developed on ridges andsomewhat less on edges.

Wood or antler. Polish on the ventral face, related tothe wooden or antler haft, was difficult to interpret. Onlyon the butt and bulb was polish sufficiently developed toallow interpretation, particularly in the case of an antlerhaft (experimental tool 11). The appearance of the polishcorresponded with use polish (smooth-pitted, slightlygrooved, bright) and it was best developed along the buttedge. Confusion with use-wear is inconceivable.

Leather bindings. Polish characteristics due to theleather bindings were not different from what has beendescribed before. The polish is rough, somewhat brighterthan expected and followed the microtopography of thesurface. Here, this pattern is even clearer, since the dorsalface was in contact with the leather (Figure 18.19).

Vegetal bindings. Lime bast bindings produced a well-developed polish, due to the prolonged use of the tool inquestion (Figure 18.20). The polish morphology wassmooth, but slightly rougher than for wood. Both can bestbe distinguished from their distribution characteristics.While both polishes follow the higher parts of themicrotopography, this polish was more extensive, well-linked and intrusive. Ridges non-parallel to the use motioncarried a far better developed polish than parallel ones,occasionally combined with a more or less extensiverounding. This trend was already observed in the first setof experiments, but not in such an obvious way.

ScarringScarring was low, with only a light crushing of the butt

Figure 18.18 Hafting striation associated with scarring ondorsal proximal butt (VBT90 2B 40–50).

Figure 18.19 Polish of leather bindings on medial ridge(experimental tool 10).

Figure 18.20 Polish of vegetal bindings on medial ridge(experimental tool 12).


observed. Fewer edges were retouched, facilitatinganalysis. The most extensive damage was observed onexperimental tool 11 because of its unretouched edgesand, more importantly, its larger tool width in relation tohaft width (27–20mm). This edge scarring clearly in-dicated the use of bindings. It was distributed in run-together patches, with very vertical scars on the right edgeand scalar feather- and step-terminating scars on the leftedge. This pattern corresponded with the path of thebindings going from dorsal left to dorsal right and over tothe ventral side. It also corresponded with the distributionof bright spots on the ventral right and dorsal left edges.Damage on the other tools was also distributed in run-together patches, but since their hafts were as wide astheir tool widths, damage was not very extensive and notvertical in nature. We mainly observed scalar feather-terminating scars.

Bright spotsBright spots were not frequent and were mostly situatedon ventral edges and surfaces, where there was directcontact with the wooden haft. Like the others, they weresmooth, flat and abrasive in nature, but mostly small(Figure 18.21).

StriationsStriations were rare, but both types (abrasive and additive)are represented. Their association with edge damage –and sometimes with bright spots (Figure 18.22) – againconfirmed the origin of the abrasive ones as due to floatingtiny chips of flint. They were mostly orientated parallelto the use motion and occured on edges and surfaces nearedges. Additive ones on the other hand, were perpendic-ularly orientated and often clearly corresponded with thehaft limit (e.g. experimental tool 10).

Rounding and smoothingRounding was only found to be present after extensiveuse (as in experimental tool 12), in zones of slight ridgedirection changes. A light smoothing due to the vegetalbindings was visible on the higher parts of the dorsal-proximal surface.

Scraping woodAnother factor that needed testing as to its influence onthe production of hafting traces was the action undertaken.Adzing is an action that applies high pressure and involveslaunching of the tool at the worked material parallel withthe long axis plane. Scraping on the other hand places ahigh load on the hafting, due to its action perpendicularto the tool’s long axis, resulting in a high pressureconcentrated in two zones: the haft limit and the butt area.

We included tools hafted with either their ventral ortheir dorsal face against the haft, and they were used inboth positive and negative scraping motions (i.e. pullingtowards the worker and pushing away respectively). Theindirect contact between experimental tool 15 and thehaft was due to a small piece of wet leather covering theventral surface and the butt, not by a real wrapping.Although all tools were used for about 30 minutes, traceswere best developed on the ridges of experimental tools15 and 16, owing to their triangular cross-section.

PolishPolish developed slower than for adzing wood, but quickerthan for adzing earth. The best-developed polish was againconcentrated on ridges, but was less present on edges andon surfaces it was hardly visible.

Wood or antler. Polish produced by a wooden or antlerhaft was most recognizable in cases of dorsal haft contactand triangular cross-sections. While polish morphologyand pattern were exactly the same as for adzing (Figure

Figure 18.21 Hafting bright spot on medial ridge (exper-imental tool 10).

Figure 18.22 Hafting striation associated with bright spotson proximal ridge (experimental tool 12).


18.23), distribution was different. It was not continuousall over the hafted part, but concentrated near the haftlimit and towards the butt.

Dried wet-leather. The same was true for polishproduced by lime bast and standard leather bindings, sowe will only consider the one resulting from dried wet-leather bindings – i.e. applied when wet and then allowedto dry, which leads to a more secure fitting throughshrinkage. The latter polish was rough and dull inappearance and less linked up in comparison with standardleather bindings. The harder nature of the dried leathercauses a better development on the outer ridge or edge,while the general pattern along the microtopographyremains the same (Figure 18.24). The insertion of an inter-mediate leather piece against the ventral face of exper-imental tool 15 did not produce an interpretable polish.

ScarringDamage was most intense on the tools’ edges and butts.Scars were generally small, irregular in morphology andvariable in termination. Scars were usually concentratedaround the haft limit and at the proximal end with a widedistribution in between. In some cases those zones evenshow crushing, as on the dorsal edges of experimentaltool 13. The haft limit is often very clear (experimentaltool 16). At the point where the tool protrudes from itshaft, edge damage can be extensive, especially in combin-ation with the harder dried leather bindings. This waswell illustrated in experimental tool 15, the only exampleshowing small scalar feather-terminating scars in a run-together distribution along the edge. Least damage wasobserved on experimental tool 14, thanks to its trapezoidalcross-section. Ridge damage was very low and onlyvisible on experimental tool 15.

Bright spotsThe amount of bright spots on these tools seemed to beinfluenced by the bindings used for fixing the tool in the

haft. Both tools fixed with vegetal bindings hardly showedany bright spots, only some tiny ones near the ridge anddorsal edge. The amount of bright spots on the other toolswas comparable to wood adzing. They were similar innature and sometimes very large and highly linked up(Figure 18.25). They occurred in association with edgescarring, sometimes accompanied by striations, onsurfaces near edges and on the edges themselves. Theyonly occured on dorsal ridges in the case of experimentaltool 13, where their presence might be linked with haftcontact. This is further confirmed by their presence onthe ridges of the archaeological scraper-adzes.

StriationsMainly the abrasive striation type was present, situatedon surfaces near edges, with no preferential orientationand associated with edge scarring and bright spots.Additive striations were nearly absent, with only a fewobserved on the proximal surface of experimental tool 14related to the antler haft. Both tools fixed with vegetalbindings virtually lacked striations.

Rounding and smoothingNo surface smoothing was present, only two instances ofrounding of ridges attributed to the leather bindings: thefirst in the medial zone of experimental tool 13 associatedwith polish, and the second on the proximal ridge ofexperimental tool 15 associated with polish and brightspots.

ConclusionsWe can conclude that the material worked and the useaction are both clearly important factors influencing theformation of hafting traces. The former mainly influencesthe rate at which hafting traces are formed, whereas thelatter affects their distribution, pattern and morphology.

In the case of adzing earth we observed less extensive

Figure 18.23 Wood hafting polish on proximal ridge(experimental tool 16).

Figure 18.24 Contact with dried leather bindings on dorsalmedial edge (experimental tool 15).


traces than in the case of wood adzing, but the morphologyand general pattern largely remained the same. Thisapplied to all the trace attributes, although rounding andsmoothing were not sufficiently developed to be character-istic. We observed less polish, scarring and bright spotsfor adzing earth. Moreover, when bright spots werepresent, they were small, clearly pointing at limitedfriction in the haft. It is obvious that the lower resistanceof earth as a worked material caused a lower impact onthe tool and its setting.

When wood adzing was compared to scraping, nosubstantial difference in trace intensity was observed.Polish development was similar, as well as scarringintensity and the amount of bright spots. The generaldistribution however, was different and was concentratedin two zones (haft limit and butt area) in the case ofscraping. Also the scar morphology and patterning weredifferent, and striations lost their preferential orientationin scraping. The slightly smaller amount of bright spotsclearly points at a lower friction in the haft, while theextent of polish, scarring and bright spots shows thatpressure on the tool and its fastening remains comparable.Consequently, it is obvious that tool use can have animportant influence on the formation of hafting tracesand that it should not be neglected. It does not, however,interfere with the recognizability of hafting traces and itsinfluence can be easily defined.

These experiments further show that general toolmorphology can have an important impact on both haftingtrace intensity and distribution. The experiments demon-strated the influence of factors such as a tool’s transverseconvexity and butt protrusion, the presence of retouchededges and tool width in relation to haft width. When itcomes to specific hafting methods, the use of a wrappinghas a noticeable influence on trace intensity.

On a more general level, it is clear that hafting tracesare produced and also that they can be recognized,something often doubted in the past. Knowledge about

whether a tool was hafted allows a whole range of furtherinferences, some of which are briefly considered here. Inthe first place, it throws light on the rarely preservedorganic part of prehistoric tools, which generally de-manded a higher time and energy investment than therelatively easily replaceable lithic part. Consequently, thisinsight into the dynamic processes of tool technology canhelp distinguish expedient technologies from curatedones, if we consider tools more likely to be hafted in thelatter case. Furthermore, we can investigate whetherstandardization in tool dimension is an important factorwhen lithic tools are hafted and whether a direct link isjustified. Finally, we are able to investigate when haftingwas introduced.

A further point is that hafting traces, in addition tobeing diagnostic as such, display patterned variabilityaccording to the exact hafting arrangement used. The latteris not only an important factor of prehistoric technology,it also allows us to investigate whether a specific haftingarrangement can be used as a chronological or culturalindicator. Furthermore, we can gain insight into theevolution of hafting arrangements and into the materialspreferentially used. If we compare the latter with environ-mental data about materials available in a specific regionand period, we can investigate which aspects may haveguided decision processes.

AcknowledgementsWe are indebted to the Onderzoeksfonds of the KatholiekeUniversiteit Leuven (OT 97/25) for their financial supportof this research. We would like to thank Ph. Van Peer forhis critical comments on earlier drafts of this paper andLes Chercheurs de la Wallonie, especially L. Pirnay, Ph.Pirson, O. Baudoux and J. Speckens, for their enormoushelp with the experiments.

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