The Unique Solutrean Laurel-Leaf Points of Volgu: Heat-Treated Or Not? Patrick Schmidt, Ludovic Bellot-Gurlet, Harald Floss

Home , Solutrean

The unique Solutrean laurel-leaf points of Volgu: heat-treated or not? Patrick Schmidt, Ludovic Bellot-Gurlet, Harald Floss

To cite this version:

Patrick Schmidt, Ludovic Bellot-Gurlet, Harald Floss. The unique Solutrean laurel-leaf points of Volgu: heat-treated or not?. Antiquity, Antiquity Publications/Cambridge University Press, 2018, 92 (363), pp.587 - 602. 10.15184/aqy.2018.87. hal-01825558

HAL Id: hal-01825558 https://hal.archives-ouvertes.fr/hal-01825558 Submitted on 12 Jul 2018

HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. antiquity 2018 Ltd, Publications Antiquity © h oura ( Solutrean The Introduction Schmidt Patrick not? or heat-treated Volgu: of points laurel-leaf Solutrean unique The ∗ 3 2 1 oyedeiec o h netoa s fha otetsoefrkapn (Bordes knapping for stone treat to heat of use intentional the for 1967 evidence yield to Keywords: otenArc,psil aigto dating possibly Africa, southern a eivdt eteods utr nweei h ol htpatsdha treatment heat practised that world the in anywhere culture oldest the (Tiffagom be to believed was utr (Flenniken culture xmlso ettetetfudaogfie-rie ok uha itadchert. and flint as such rocks finer-grained among found treatment heat of examples neatose Spectroscopies’ et Interactions Universités Sorbonne Tübingen of University Karls Eberhard Tübingen of University Karls Eberhard oetbne,700Tübingen 72070 Hohentübingen, 27 Tübingen 72074 uhrfrcrepnec (Email: correspondence for Author , 1969 233(08:587–602 (2018): 363 92 rne oura,lue-efpit,ha ramn,fln,infrared flint, treatment, heat points, laurel-leaf Solutrean, France, 1998 .Utltercn noneeto ettetd ore-rie iceefrom silcrete coarser-grained heat-treated, of announcement recent the Until ). , nzn&Tixier & Inizan ; Paris c Germany 21k)i h aletkonpro fteErpa Palaeolithic European the of period earliest-known the is 22–18ka) . , 1987 1,2, PCUiest ai 6 Paris Université UPMC Volgu ∗ , ,teSltenapast aepoie oeo h earliest the of some provided have to appears Solutrean the ), uoi Bellot-Gurlet Ludovic , M 8233 UMR 0 , km [email protected] Germany 200 , , 2001 , eateto Geosciences of Department UPMC-CNRS eateto al rhsoyadQaenr Ecology Quaternary and Prehistory Early of Department N c 6k tPnal on (Brown Point Pinnacle at 164ka . .Nvrhls,aogwt h ieinDyuktai Siberian the with along Nevertheless, ). , 587 OAI d aMlcl u aoojt:Réactivité, Nano-objets: aux Molécule la ‘de MONARIS ye enn htw utrtikthe rethink used was must technique a we such tool why reasons that particular meaning this not type, to was applied treatment heat universally that Volgu The show spectroscopic assumption. the findings this test from infrared to artefacts conducted cache an seven of of analysis presents results study the have This both assemblages. as with Solutrean association points, in the described helped previously of been have making may the in treatment the pressure heat of to flaking, addition period In Solutrean Palaeolithic. Upper the from known craftsmanship cache skilled of Volgu examples most remarkable the among the rank France eastern of in found points laurel-leaf The , lc Jussieu place 4 3 ) , aadFloss Harald & ple Mineralogy Applied https://doi.org/10.15184/aqy.2018.87 75252 , ai ee 5 Cedex Paris , tal. et ihlsrß 56, Wilhelmstraße 1 , France 2009 , . Schloss ,it ),

Research Patrick Schmidt et al.

Bifacial laurel-leaf points, or feuilles de laurier, are the type-fossil of the Solutrean, and are also the most commonly found artefacts from this period to bear evidence of heat treatment. The production of some of these thin points involved a further step of pressure knapping to refine their shape (Aubry et al. 1998), thereby requiring a relatively high level of technical skill. The appearance of these objects during the Last Glacial Maximum marks the earliest evidence for the pressure-flaking technique in Europe (Darmark 2011). Several examples from south-western France (Bordes 1969) and Spain (Tiffagom 1998) document thermal treatment as part of the later stages of the chaîne opératoire associated with their production. The benefits (and in some cases, perhaps requirement) of heat alteration of flint for pressure flaking has been detailed by several authors (e.g. Crabtree & Butler 1964; Flenniken 1987;Darmark2011). Heat treatment has therefore traditionally been considered as an expression of high technical skill and investment, associated with the production of an elaborate tool kit. The exceptional degree of technical skill and considerable investment of time and effort given over to Solutrean tool manufacture is apparent in the famous laurel-leaf points of the Volgu cache in eastern France (commonly called ‘feuilles de Volgu’). The points reach up to 350mm in length without exceeding 10mm in thickness, and are among the largest and most skilfully worked of all known Solutrean points. Furthermore, although some of them may have been produced using only direct percussion, others are reported to show traces of pressure flaking (Bordes 1968). This raises the question of whether Solutrean knappers also heat-treated their raw materials to help in the production of these extraordinary tools. If the Volgu points were knapped from heat-treated flint, the overall investment required for their production must have been even greater than previously thought. If they were knapped from unmodified flint, we must rethink the assumed association between pressure flaking and heat treatment in the Solutrean, and adjust our understanding of the role of the latter, con- sidering it either as a technical necessity or as a sophisticated optional approach applied to specific raw materials. In order to answer this question, we present the results of a novel and non-invasive method for detecting past heating events in the fine-grained silica rocks used for the Volgu points curated at the Musée Vivant Denon in Chalon-sur-Saône (France).

Methods and materials The Volgu points and their origin The Volgu points were discovered in 1874 during construction work in the hamlet of Volgu, in the commune of Rigny-sur-Arroux, 80km west of Mâcon, France (Chabas 1874). Initially believed to be Neolithic in date (Rutot 1905), they are now widely recognised as belonging to the Solutrean techno-complex, based on the technological and typological afﬁnities of the assemblage established by Abbe Henry Breuil (1908). They were found beneath approximately 1m of sediment deposited on the east bank of the Arroux River, a tributary of the Loire. The ﬁnd has been the subject of many publications and theses since its discovery (e.g. Bonnet 1904;Jost1927; Cabrol 1940; Armand-Calliat 1950;Smith 1966; Blake 2010;Inada2014), most of them concerning the age, the number of points found or the nature of the archaeological context. Today, 13 Volgu points are housed in the Musée Denon in Chalon-sur-Saône (France), one in the British Museum and another © Antiquity Publications Ltd, 2018

588 olce a aeilsmlsadcmae hmwt h og ons Aubry points. Volgu the (Schmidt with treatment them compared heat and detecting ( samples for material used raw method collected the calibrate To samples Geological points. Volgu the and cache the with connection obvious any show but collection, (Masson Volgu origin the in to Mesoamerican belong as to identified believed been (Jost subsequently originally has preserved was Lyon, are in Cabrol which naturelle (e.g. of d’histoire sources also two-thirds some are in about mentioned There point, are Volgu Paris. other near one Germain-en-Laye 1927 least St at in of nationale reports d’Archéologie Musée the in sete tltra rrta eois eea te oura ie aeas enfudin found been also have Desbrosse sites & Solutrean (Peyrouse Volgu other of Several vicinity deposits. the ritual or from utilitarian numbers larger (Kilby either in as culture known Clovis are caches American Such North cache. or the deposit intentional an was this that eaet onsecue rmoraayi,w ol o niiaemjrcagst the to changes major anticipate Aubry not study. would present we potentially the analysis, data of new our raw the outcome from because another excluded and to points Peyrouse concerns, to points this (J.-B. Volgu Turonian) relate point which Lower the unclear (also of remains Valley one it Cher present, of the assignment in unpublished, origin far material Aubry so in yet found possible, be a can others the to grey-black from two and flint, light-brown yellowish, Chalon- of ( in still made flint curated are are points Volgu which five the of these, of (12 seven Of points analysed sur-Saône. its have we of study, preservation present and the for For quality exceptional intact). high is size, a cache Volgu the materials, the of points, raw combination laurel-leaf the of larger yielded types have two France western from from made were (‘ flint Chalon-sur-Saône light-brown in yellowish, Denon Volgu Musée the the Tours, embed (Aubry in around River to regions Saône the sought between the strategies and studies migration Gien Solutrean sourcing of The network a analysis. within cache provenance material raw and yeo itfo h oe uoincaklyr rudGe,aot10mt the to 150km about Gien, around layers Aubry chalk Turonian 1; group Lower (micro-facies the Volgu of from north-west flint of type a rvdstems euedt o u td tti time. this at study our for data secure most the provides aeilue o h w rybakpit mcoaisgop3 a o dnie with identified not was 3) group (microfacies points grey-black two certaintybyAubry the for used material it n ye2 rybakfln.Prso ittp arsoial eebeteraw light-brown the yellowish, resemble macroscopically a 1 1, type observed flint type we of profile: outcrop, Parts the flint. primary grey-black with this a associated 2, at type directly fieldwork and flint During flint; Briare. of and types Gien two of towns the 2003 eety h onshv entesbeto ealdtcnlgclsuis(Inada studies technological detailed of subject the been have points the Recently, h og onswr on ragdurgtadsd-ysd namne suggesting manner a in side-by-side and upright arranged found were points Volgu The her ur ( Aubry Thierry g ) u h rgnlnme fpit a vnhv enhge:u o3 pieces 30 to up higher: been have even may points of number original the but 1), fig. : iue1 Figure rvosyietfidterwmtra ftefieyloih ih-rw onsas points light-brown yellowish, five the of material raw the identified previously ) ; al 1 Table h nqeSltenlue-efpit fVlu ettetdo not? or heat-treated Volgu: of points laurel-leaf Solutrean unique The es comm. pers. tal. et ). ( 2003 ie blond silex idypoie h ou ftegop1mtra between material 1 group the of locus the provided kindly ) ,adol h ointa hs it aeasmlrtexture similar a have flints these that notion the only and ), tal. et tal. et tal. et )adadre,ge-lc it lhuhohrsites other Although flint. grey-black darker, a and ’) 2003 s( ’s 2014a 589 ( 1940 2007 2003 ;Peyrouse 2003 .Aohrpit osdi h Muséum the in housed point, Another ). ;Peyrouse .W aercnl enmd wr of aware made been recently have We ). ) hr hyhv eninterpreted been have they where b), & tal. et a aeilpoeac ceethus scheme provenance material raw ) tal. et 2003 tal. et niut ulctosLd 2018 Ltd, Publications Antiquity © 2013 .Tepoeac fteraw the of provenance The ). 2013 .Te1 onshoused points 13 The ). 1984 ),butnoneofthem tal. et ). es comm. pers. 2013 2014 ,we ), tal. et .At ). )

Research Patrick Schmidt et al.

Figure 1. Photographs of both faces of two of the Volgu points (left: 2011-0-12-4; right: 2011-0-12-5) made from the two raw material classes. The photographs were taken in water so that removal negatives are not visible and that features in the raw materials can be appreciated (photographs by Patrick Schmidt). material used for the five lighter Volgu points, in that they are similar in colour and contain lighter matt parts and micro-fossil inclusions. Although Aubry et al.(2003) distinguished the raw material of the two darker coloured Volgu points from the others, flint type 2 macroscopically resembles them. A detailed micro-palaeontological analysis of these raw materials lies beyond the scope of our study. The results obtained from the two grey-black points are just indications, and their confirmation must await the secure assignment of the origin of the darker raw material. Twenty-seven samples were collected from a primary position reflective of the variability in the macroscopic appearance of the flint from this outcrop. Thirteen were yellowish, light-brown flint, and 14 were grey-black flint. Although no systematic knapping experiments were undertaken, it appeared clearly during collecting and testing these samples (tentatively fracturing the samples with a hammer) that they have excellent properties for knapping. © Antiquity Publications Ltd, 2018

590 ubrnme ai ratio ratio number number apeaayi 4545/4469cm analysis Sample Ma ai’rfr oteaeaeo l 4545/4469cm all of average the to refers ratio’ ‘Mean The points. laurel-leaf Volgu seven elgclrfrnenme ai ratio ratio number reference Geological acltda aiu n iiu xesoso l ai ausue ocluaetemean. the calculate to used values were ratio values all ratio of mean extensions these minimum after and stated maximum Ranges as group). calculated samples reference geological or (sample rybakflint grey-black of reference Geological flint light-brown yellowish, of reference Geological 4545/4469cm near-infrared the of Results 1. Table flint) (yellowish 2011-0-12-4 h nqeSltenlue-efpit fVlu ettetdo not? or heat-treated Volgu: of points laurel-leaf Solutrean unique The ± .1rneo igertovle eet h esrmn error. measurement the reflects values ratio single of range 0.01 Arbitrary i1-70.7879 0.7966 0.7909 0.7867 0.8059 Gi-15-27 0.8102 Gi-15-26 0.8036 Gi-15-25 0.8064 Gi-15-24 0.7989 Gi-15-23 0.7832 Gi-15-22 0.7936 Gi-15-21 0.7925 Gi-15-20 0.7968 Gi-15-19 0.8111 Gi-15-18 Gi-15-17 0.7966 Gi-15-16 0.8329 Gi-15-15 0.7889 Gi-15-14 0.8064 0.7707 0.8227 Gi-15-13 0.7916 Gi-15-12 0.7891 Gi-15-11 0.7999 Gi-15-10 0.7997 Gi-15-9 0.8202 Gi-15-8 0.8294 Gi-15-7 0.8073 Gi-15-6 Gi-15-5 Gi-15-4 Gi-15-3 Gi-15-2 Gi-15-1 og arlla points laurel-leaf Volgu ape4545/4469cm Sample 0.7785 0.8245 4 3 0.762 0.8136 2 1 0.7763 6 0.8058 5 591 − 1 − ai fgooia eeec ape n the and samples reference geological of ratio 1 ai ausfo ihnagvngroup given a within from values ratio niut ulctosLd 2018 Ltd, Publications Antiquity © ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 .10.7979 0.01 0.01 0.01 0.01 0.01 0.01 − − 1 1 ± 0.7974 − + 0.8043 Mean + 0.014 0.034 / 0.029 − Mean .3 / 0.033 0.036

Research Patrick Schmidt et al.

Table 1. Continued. Volgu laurel-leaf points Arbitrary Sample analysis 4545/4469cm−1 Mean number number ratio ratio

7 0.8305±0.01 8 0.7920±0.01 1 0.7975±0.01 2 0.7744±0.01 3 0.8031±0.01 0.7957 2011-0-12-5 4 0.7827±0.01 +0.012 / (black ﬂint) 5 0.8074±0.01 −0.021 6 0.7905±0.01 7 0.8038±0.01 8 0.8062±0.01

1 0.7840±0.01 2 0.7981±0.01 3 0.7880±0.01 0.7842 2011-0-12-8 4 0.7640±0.01 +0.014 / (yellowish ﬂint) 5 0.7637±0.01 −0.02 6 0.7828±0.01 7 0.7975±0.01 8 0.7951±0.01

1 0.7618±0.01 2 0.7726±0.01 3 0.7823±0.01 0.7740 2011-0-12-9 4 0.7710±0.01 +0.008 / (yellowish ﬂint) 5 0.7767±0.01 −0.012 6 0.7706±0.01 7 0.7805±0.01 8 0.7764±0.01

1 0.8015±0.01 0.8027 2011-0-12-10 2 0.7765±0.01 +0.024 / (black ﬂint) 3 0.8067±0.01 −0.026 4 0.8263±0.01

1 0.8025±0.01 2 0.8017±0.01 3 0.8036±0.01 0.8054 2011-0-12-11 4 0.8090±0.01 +0.014 / (yellowish ﬂint) 5 0.8190±0.01 −0.012 6 0.7930±0.01 7 0.8090±0.01

592 ubrnme ai ratio ratio number number rnmsin nyabifsmayo h ehdi rvddhr;frhrdtiscnbe can details further here; provided is method Schmidt the in of found treatment. summary heat brief after a knapped Only was surface transmission. it strong whether or of of intermediate estimation weak, lustre permit overall of surface may 2) identification artefact the an The is of on artefact. magnitude criterion a gloss an overall macroscopic on behind the scars only leaving of removal the estimation scars, all case, qualitative removal a the pre-heating intensity: such all gloss not, In does remove after surface. retouch contrast may glossy or gloss invasive, homogeneous knapping of because if absence heat-treated treatment, not The was removals. heat material shiny between the modified and on that were indicate matt contrast post- rock however, because the gloss the glossier treatment of of such heat mechanics or detachment of identifying fracture the shinier presence for the that criterion The and would indicates macroscopic artefact. pre- unambiguously secure proxies an it most matt observable of the of two is side artefact only presence one an on the coexistent scars points, the removal Volgu contrast: heating the gloss overall of and 1) contrast case gloss be the treatment: heat In of proxies intensity. two gloss for inspected first were artefacts All set-up experimental and Methods flint) (yellowish 2011-0-12-12 Continued. 1. Table apeaayi 4545/4469cm analysis Sample hf olwrwvnmes hl espr ae assasitt ihrwavenumbers higher to shift a to band causes SiOH water the pore causes less water while pore (Schmidt of wavenumbers, amounts lower and Greater water to walls. pore shift pore between samples. bonding) the the (hydrogen on of interaction pores SiOH chemical open surface the interconnected is the this in for held reason water The of quantity the by influenced is hnadmd ftasuetfln,i spsil oeaieams h nievlm of volume entire 4800cm the and 4000 almost (between band examine the combination in to SiOH spectrum a possible absorption of infrared is range an both produce are it measurements which non-invasive flint, points, The Volgu point. translucent the each of of case made the and In thin. thin sufficiently if stone, through radiation hna nietmaueo h uniyo ae edi pnpores. open in held water of quantity the of measure indirect an then w ierasrac ausa 4545cm at values absorbance linear two h og onswr hnaaye o vdneo ettetetuigifae light infrared using treatment heat of evidence for analysed then were points Volgu The tal. et h nqeSltenlue-efpit fVlu ettetdo not? or heat-treated Volgu: of points laurel-leaf Solutrean unique The 2011 tal. et .Tesaeo hsasrto adi esrda h ai between ratio the as measured is band absorption this of shape The ). ( 2013 Arbitrary .Temto esrstetasitneo near-infrared of transmittance the measures method The ). 0.7787 0.7601 0.7531 0.7640 0.7795 0.7723 0.7574 0.7671 8 7 6 5 4 3 2 1 og arlla points laurel-leaf Volgu − 1 593 n 4469cm and − ± ± ± ± ± ± ± ± 1 h 4545/4469cm The . .10.7665 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 niut ulctosLd 2018 Ltd, Publications Antiquity © − − 1 1 .Tesaeo hsband this of shape The ). − ± 1 Mean 0.013 ai is ratio

Research Patrick Schmidt et al.

In order to take these measurements, all available pore space is artiﬁcially saturated with water. The ratio is then a measure of the total volume of the open pore space of the sample. Such measurements can be used to detect past heating events because pore space is gradually lost when stone such as ﬂint and chert are heat-treated (Roqué-Rosell et al. 2010; Schmidt et al. 2012). Interpretation of the ratio must be made through a direct comparison with a corresponding value obtained from a reference sample of the same material that has not been heated. The two samples compared in this way (the one tested for past heating, and the reference) must undergo an identical protocol that allows the open pore spaces to be totally −1 saturated with deionised or distilled H2O. If a higher value of the 4545/4469cm ratio is found in the tested sample to that of the reference sample, then this indicates that the tested sample was subjected to heating. Thus, this method uses comparative measurements of the open pore space to detect past heating events. It is entirely non-destructive and allows for fast and cost-effective analyses. To apply this method to the seven selected Volgu points and 27 geological reference samples, each was hydrated in deionised H2Ofor72hoursat20°C and at an ambient pressure to saturate their open pore space with water. Spectra were acquired directly after the points were removed from the water, the surface dried with paper, so that the pore space had no time to dehydrate. Measurements were taken in two stages. The seven artefacts were analysed at the Musée Vivant Denon (Chalon-sur-Saône), and the geological reference samples were analysed in the MONARIS Lab (Paris). The same conditions (temperature and duration of the hydration) were maintained to ensure the comparability of results.

Analytical equipment and experimental error The infrared transmittance was recorded through the samples at normal incidence using the unpolarised light of a portable Bruker ALPHA spectrometer. Spectra were acquired between 4000 and 5000cm−1 with a resolution of 8cm−1. For the measurements, the portable spectrometer was placed on one of its lateral sides so that the entrance to the sample chamber was oriented horizontally. The Volgu points were then placed on a pedestal in front of the spectrometer, with the extremities where the measurements were to be performed pointing into the sample chamber (Figure 2). No other sample preparation was necessary, and the analyses of all archaeological samples were completely non-destructive. For each artefact, several measurements (between 4 and 8, see Table 1) were taken at different locations in order to encompass the possible range of variability within the raw material and to assess the consistency of the results. Experimental errors on the 4545/4469cm−1 ratio were taken from Schmidt et al. (2013) as a ﬁxed ratio value of ±0.01.

Results Description of the artefacts Six of the analysed pieces are intact laurel-leaf points; the seventh is broken with approximately two-thirds extant. The points are broadly symmetrical along their longitudinal axis and have an elongated and ﬂat sub-oval cross-section. The six intact pieces measure 230–340mm in length, 62–94mm in breadth and 7–12mm at their thickest © Antiquity Publications Ltd, 2018

594 n w og arlla points. laurel-leaf Volgu two and 3 Figure analysis Spectroscopic (Pelegrin removal Pelegrin percussion (J. sub-parallel soft-hammer ends mostly distal direct their The of on flaking point. indicative 190g, are larger weighs points much 1981 fragment Volgu a broken the originally the on and was negatives 128–181g, it weigh that each indicating points intact The points. this within points Volgu the of placement the and spectrometer, the of Schmidt). position Patrick and by set-up (photograph the arrangement showing Photograph 2. Figure fte2 a aeilsmls ntebsso hsassmn,nn ftepit show points the of none assessment, this of basis treatment. heat the that of On resembles signs contrast samples. points macroscopic no seven material any showed all raw of also 27 intensity and gloss the examined overall were of The points reflectivity. light the or of shininess each of gloss of of ends indication distal no revealed The conditions contrast. two raking-light and the vertical- different between in points differences Volgu obvious no with rare. arranged are cortex similarly of Traces are faces. points Volgu the of ewe .7 n .3,stigterneo ai auso h netdlgtrTuronian lighter unheated the of are values values ratio between of plotted to range All flint the setting points. 0.833, Volgu and seven 0.771 between the and samples in reference summarised geological 27 the of ih-rybrin bar light-grey 1)poue ai ausbten073ad081 n h w rybakpoints grey-black two the and 0.831, and 0.753 between values ratio produced in -12) bar flint grey Turonian darker darker smaller, unheated, (the the 0.77–0.82 of approximately values of and ratio range of narrower range a the to setting 0.811, and 0.783 eadn h osbepoiso ettetet arsoi bevto fteseven the of observation macroscopic treatment, heat of proxies possible the Regarding h v elws,lgtbonVlupit 21--24 8 9 1 and -11 -9, -8, (2011-0-12-4, points Volgu light-brown yellowish, five The iue5 Figure ,atog oeo h icshv enitrrtdt hwidctoso pressure of indications show to interpreted been have pieces the of some although ), hw h rnmsinsetarcre rmtregooia eeec samples reference geological three from recorded spectra transmission the shows ). al 1 Table h nqeSltenlue-efpit fVlu ettetdo not? or heat-treated Volgu: of points laurel-leaf Solutrean unique The ∼ iue4 Figure .6and 0.76 elws,lgtbonfln eeec ape rdcdrtovalues ratio produced samples reference flint light-brown Yellowish, . .Ge-lc itrfrnesmlspoue ai ausbetween values ratio produced samples reference flint Grey-black ). ∼ .4i h esrmn ro stknit con telarger (the account into taken is error measurement the if 0.84 iue4 Figure es comm pers. 595 sapo fte4545/4469cm the of plot a is ) eaie ntetpadbto sides bottom and top the on Negatives .). niut ulctosLd 2018 Ltd, Publications Antiquity © − 1 ai values ratio iue4 Figure

Research Patrick Schmidt et al.

Figure 3. Near-infrared spectra recorded from the geological reference (bottom three spectra) and two of the Volgu laurel-leaf points (top). The spectra are vertically offset for clarity.

(2011-0-12-5 and -10) produced values between 0.774 and 0.826. All archaeological samples thus fall within the range of the unheated reference materials, suggesting that they have not previously been heated. The mean ratio values calculated from the measurements of each sample and reference sample are shown in Figure 4. These values give a narrower range of reference values than those produced by the two groups of geological reference samples because the estimated measurement error is not taken into account. These mean ratios yield the same result: all of the Volgu points fall within the range of the unheated reference samples. © Antiquity Publications Ltd, 2018

596 ntosmlrsuis n nha-rae eiaefo h rnhNoihcChassey Neolithic French the from (Schmidt debitage Saint-Martin heat-treated of site on the one from culture studies, similar two In Discussion 4545/4469cm the of values the of Plot 4. Figure r ipae ntelf ftegah h ag fvle rdcdb hs netdsmlsi akdb rybr (light bars heated. grey not by were they marked that is demonstrating samples range, unheated this these within by fall produced mostly points values Volgu of the flint) range grey-black by The the graph. and flint the Ratio light-brown piece). of yellowish, grey per left (the measurements samples the eight reference on or geological seven displayed unheated (four, are the points laurel-leaf of Volgu categories seven both the of of values values the with compared sample) per eeec apeadteha-rae rhelgclmtra nteCasysuywas study Chassey the in material archaeological unheated heat-treated (Schmidt the of the 0.078 ratios and mean the Morala sample between & difference reference The (Schmidt values. Laugerie-Haute sample reference of respective site the from 2018 points laurel-leaf Solutrean treated oprbei h he tde:Casyrfrnevle alwti ag of range a within fall values reference Chassey studies: three the in comparable (Schmidt ( Morala and Schmidt in data the n agreHue tflosta fteVlusmlswr etd hywudgv an mean give the above would values. 0.08 they reference approximately heated, and unheated were 0.05 the approximately of samples between Volgu of the value if ratio that average follows it Laugerie-Haute, within and values reference Volgu and = ,rtovle rdcdb ettetdacaooia ape i bv hto their of that above lie samples archaeological heat-treated by produced values ratio ), ag rdcdb elws,lgtbonfln,dr grey dark flint, light-brown yellowish, by produced range tal. et h nqeSltenlue-efpit fVlu ettetdo not? or heat-treated Volgu: of points laurel-leaf Solutrean unique The 2013 tal. et ,Luei-at auswithin values Laugerie-Haute ), 2013 ,ad00 nteLuei-at td rcluae from (recalculated study Laugerie-Haute the in 0.05 and ), 2018 ± − .3 ntebsso h eut rmSaint-Martin from results the of basis the On 0.03. 1 ai bandfo h elgclrfrnesmls(n measurement (one samples reference geological the from obtained ratio ) h ag fuhae eeec ausi also is values reference unheated of range The )). 597 = tal. et ag rdcdb rybakfln) h ausproduced values The flint). grey-black by produced range 2013 ± .1(cmd Morala & (Schmidt 0.01 ,adteohro mle,heat- smaller, on other the and ), niut ulctosLd 2018 Ltd, Publications Antiquity © ± 2018 0.02 )

Research Patrick Schmidt et al.

Figure 5. Plot of the mean values of the 4545/4469cm−1 ratio of geological reference samples and Volgu laurel-leaf points. These mean ratio values are the average values of each sample (for the Volgu points) or group (the yellowish, light-brown ﬂint and the grey-black ﬂint). Error bars for the values mark the minimum and maximum extensions of the ratio values used to calculate the mean. The range of values produced by these unheated samples is marked by grey bars, as in Figure 4,butthe bars are smaller because they do not take into account the estimated ±0.01 measurement error. In this plot the Volgu points also fall within this range, demonstrating that they were not heated.

Given the ±0.03 ratio range for our reference samples from the Gien region, it would be possible to detect such a difference because the artefact measurements would fall outside the range of non-heated reference values. Instead, none of the Volgu point measurements plot above the range set by the reference values (Figure 4). Thus, compared with the Saint- Martin and Laugerie-Haute results, which indicate heat treatment, our data clearly show that the Volgu points were made from unheated flint. A potential source of error that requires consideration may arise from the suitability of our geological reference samples. Aubry et al. (2003) state that the Volgu points were produced using flint from the alteration horizons of the Lower Turonian of the Gien region; this is a secondary geological position. Instead, the flint used for reference in this study was sourced directly from the Lower Turonian chalk layers, a primary position. Weathering of flint-bearing carbonaceous layers (carbonate leaching of the host rock) was reported to alter the crystallography of the included flint through dehydroxylation (Fernandes et al. 2012). Our archaeometric method is sensitive to the loss of hydroxyl (Schmidt et al. 2013), and geological dehydroxylation might result in slightly increased 4545/4469cm−1 ratio values in flint from alteration horizons. In some cases, it may therefore be expected that flint from the latter, when compared with the same flint from the primary position (before © Antiquity Publications Ltd, 2018

598 ocnrdc rvosacaooia n xeietlsuis(..Cate Butler & Crabtree (e.g. studies separate experimental and and choices archaeological interpreted 1964 heat, be independent flaking. could previous by finding pressure as This contradict situations. using modified viewed specific to in stage not be applied manufacturing were therefore were that final processes should technical here a techniques analysed undergo two did points laurel- These them crafted Volgu skilfully of the most some and today, although largest treatment known the heat Among between points association Solutrean. strict leaf the no in was flaking there pressure that suggest and study this of results The Solutrean the for Implications Aubry of resolved spite be in cannot uncertainty If, issue the this analysis. material, material of raw raw view grey-black for further In however, the without -10. persists, of and provenance Doubt 2011-0-12-5 the heat-treated. surrounding not artefacts: were grey-black-coloured indicate points two unambiguously Volgu they the analysed that meaning seven scenario, the second that the to correspond results Our values, reference the as range same the in plot values ratio artefact the however, samples, If, reference 2) the of values the above plot artefacts the of values ratio been the not has If that position 1) primary possible: are the scenarios dehydroxylated from two such material dehydroxylated, from reference made with were such compared If artefacts when treatment. if heat flint, and modest flint, for the mistaken in be occurred may dehydroxylation that signal a produce would alteration), atog h eainbtenha ramn n rsueflkn a o aebe so been have not Aubry may example, flaking for pressure see, Solutrean; and the treatment in heat strong between relation the (although two these for treatment heat of indications no are there stands, it hypotheses values artefacts. two As point the lighter-coloured probable. of the former more the of that is range suggesting the possibly a within microstructure, of similar lie the our is a that points indicates fact material grey-black Gien, The raw two values. from darker the reference suitable of this flint new ratios If produce darker-coloured confirmed. must studies be the future will origin, to different artefacts correspond two these points concerning two results these contrary, the auatr a aebe fsfcetqaiyt lo rsueflkn ihu h need the without flaking pressure allow to treatment. quality heat sufficient for of been have may manufacture h eeec aus fti snttecs,te vni reat eekapdfrom knapped have were above could artefacts plot treatment if also heat even or would then dehydroxylation case, values significant the occurred. ratio no reference not the flint, artefact the is position the this If of secondary subjected If heated, those heated. was values. above were reference flint not plot artefacts the this would were the if values If and artefacts ratio values. flint, artefact the position the that dehydroxylation, secondary to from indicating knapped unambiguous, were artefacts is result the reference with might dehydroxylated. compared not values is being that artefact are position primary position Higher the secondary from treatment. from material the knapped heat artefacts from that of flint indicate also dehydroxylated however, diagnostic might, They be treatment. heat not indicate may results the ;Darmark h nqeSltenlue-efpit fVlu ettetdo not? or heat-treated Volgu: of points laurel-leaf Solutrean unique The 2011 hthv yohssdacoeascaino ohtechniques both of association close a hypothesised have that ) 599 tal et . 2008 .Terwmtra sdi their in used material raw The ). niut ulctosLd 2018 Ltd, Publications Antiquity © tal. et s( ’s 2003 supinto assumption )

Research Patrick Schmidt et al.

The absence of heat treatment in the production of the Volgu points may be explained by regional differences in technological practice within the Solutrean. Most identifications of heat treatment from this period come from west and south-west France (e.g. Bordes 1969; Aubry et al. 1998) and the Iberian Peninsula (e.g. Tiffagom 1998). There is little published evidence for heat treatment related to specific Solutrean sites, and there may be zones within the spread of the Solutrean techno-complex where heating was more common than others. To answer this question will require a larger-scale systematic study. Finally, the decision to not heat-treat these exceptionally well-crafted points could be due to the risk associated with this process. Knapping such points probably required a considerable investment in time. The application, even of well-controlled heat treatment, might pose considerable risk if the preforms were to overheat or break during the heating process. The high investment necessary for knapping the Volgu points may therefore ultimately be the reason why they were not heated. What appears certain is that heat treatment was a sophisticated technical solution that was not universally applied to leaf-shaped points in the Solutrean. The results of this study suggest that it was neither explicitly associated with pressure flaking nor with the production of aesthetically or functionally sophisticated pieces. On the current evidence, it seems, rather, to have been a technique specific to the Solutrean in Europe, previously unknown and subsequently forgotten again, and, much like pressure flaking, was used for very particular purposes.

Acknowledgements We thank the Musée Vivant Denon in Chalon-sur-Saône for providing access to the seven Volgu points and for facilitating our measurements inside the museum, and particularly Gwenaëlle Marchet-Legendre, Catherine Michel and Denis Dubois for greatly aiding our work there. Financial support for P.S. was provided by the Deutsche Forschungsgemeinschaft (DFG) (grant numbers SCHM 3275/2-1 and CO 226/25-1, MI 1748/2- 1, NI 299/25-1). We also thank T. Aubry for his help with locating a suitable raw material outcrop for this study.

References Aubry, T., B. Bradley, M. Almeida, B. Walter, M. Joao Neves, J.M.L. Pelegrin & M. Tiffagom. Armand-Calliat, L. 1950. Catalogue des collections 2008. Solutrean laurel leaf production at archéologiques: 19. Chalon-sur-Saône: Editions du Maîtreaux: an experimental approach guided by Musée de Chalon-sur-Saône. techno-economic analysis. World Archaeology 40: Aubry, T., B. Walter, E. Robin, H. Plisson & 48–66. M. Ben-Habdelhadi. 1998. Le site solutréen de https://doi.org/10.1080/00438240701843538 plein-air des Maitreaux (Bossay-sur-Claise, Blake, E.C. 2010. Stone ‘tools’ as portable Indre-et- Loire): un faciès original de production sound-producing objects in Upper Palaeolithic lithique. Paléo: 163–84. contexts: the application of an experimental study: Aubry, T., J.-B. Peyrouse & B. Walter. 2003. Les 332. Unpublished PhD dissertation, University of feuilles de laurier de Volgu (Saône-et-Loire): une Cambridge. énigme en partie résolue? Paléo 15: 251–54. Bonnet, G. 1904. Étude sur le Charollais préhistorique. Annales de l’Académie de Mâcon IX: 336–419.

600 Bordes Inada 1968. – Inizan Chabas Cabrol Flenniken Brown Breuil Solutréen. au silex du thermique Traitement 1969. – Crabtree Darmark Fernandes Anthropology Siberia. of technique blade https://doi.org/10.3406/paleo.2000.4707 roches des siliceuses. thermique traitement le feu: du 25–55. Paléolithique. le dans techniques aScéépéitrqefrançaise préhistorique Société la (Saône-et-Loire). Volgu laurier’ de de solutréennes ‘feuilles des faconnage de processus ultnd aScéépéitrqefrançaise 186–89. préhistorique Société la de Bulletin (Saône-et-Loire). Volgu de solutréennes pointes Meyer M.C. Jacobs Z. https://doi.org/10.1126/science.1175028 859–62. humans. 325: modern early of tool engineering FQAFe qian u3 a u1juin 1 au mai 2012. 30 du Aquitaine en Excursion AFEQ—ASF récents. travaux les sur un point d’Aquitaine: continental presented Quaternaire Paper the question. at la de état Bergeracois: du Diana Bulletin française préhistorique Société la de Bulletin ’rhooi eChalon-sur-Saône de d’archéologie Digoin près (Saône-et-Loire). Volgu à silex de d’armes ..Séronie-Vivien M.R. of treatment materials. heat silica 1 knapping: flint in experiment odeh edleg&Lno:Springer. London: & Heidelberg & Dordrecht to origin experimentation from modern making, blade pressure of emergence (ed.) Desrosiers P.M. in of points, production projectile the in element of technological evolution a and diffusion innovation, the mapping , , , , T. , , , M.L. h l tn Age Stone old The A.H. K.S. F. F. M.A. , 04 ettto tcrcéitqe des caractéristiques et Restitution 2014. , K. , 97 osdrtossrl yooi tles et typologie la sur Considérations 1967. D.E. , 84 e ie eVlu Découverte Volgu. de silex Les 1874. J. P. , , & 98 accet eL Goulaine. La de cachette La 1908. 01 ufc rsueflkn nEurasia: in flaking pressure Surface 2011. Paléorient ..Marean C.W. , 97 h aelti yka pressure Dyuktai Paleolithic The 1987. 90 rpsd adcuet des découverte la de propos À 1940. .Tribolo C. .Morala A. .Tixier J. & 4 117–32. 24: & 5 268. 15: ..Butler B.R. Tebiwa h nqeSltenlue-efpit fVlu ettetdo not? or heat-treated Volgu: of points laurel-leaf Solutrean unique The .Bernatchez J. apr ascéédhsor et d’histoire société la à Rapport 6 23–36. 26: e ok McGraw-Hill. York: New . 01 ’mrec e arts des L’émergence 2001. . & , , 6–3 e ok& York New 261–83. : :1–6. 7: .Braun D. .Schmidt P. , .Turq A. ...Herries A.I.R. ora fArctic of Journal 94 oe on Notes 1964. . 1:433–52. 111: 09 iea an as Fire 2009. . 24. : Quartär 02 esilex Le 2012. . , ..Roberts D.L. , ultnde Bulletin The , 18: 37: 6 197. 66: Science , 601 Peyrouse Peyrouse Pelegrin Roqué-Rosell Masson and blades Clovis on perspective regional A 2014b. – Schmidt Schmidt Schmidt Kilby Jost Rutot ultnd aScéédHsor auel tdsamis des d’Autun et Muséum Naturelle du d’Histoire Société la de Bulletin (Saône-et-Loire). Volgu à solutréennes pièces 6otbe1nvmr 2007 novembre Preuilly-sur-Claise octobre–1 ‘66, 26 Smith après ans 40 Solutréen, ligérien. Bassin le déplacements dans les solutréens sur indices nouveaux de revisité!: Llach Mangado X. leaves’. ‘laurel auel eLo,2èesupplément 22ème Lyon, de naturelle Volgu’. Science treatment. heat flint upon in chalcedony sedimentary of h c transformations i l h ö Fr F. Bourhis Le E. olg tto:TxsAMUiest Press. University understanding A&M Texas new Station: a College of edge (ed.) Jennings the T. on & Clovis: Smallwood A. in caching, blade Mexico. New of University research new and (ed.) discoveries Kilby J.D. & Huckell in B.B. landscape, Clovis-age raw the lithic on and materials people of movement the caching: https://doi.org/10.1016/j.saa.2011.06.050 Spectroscopy and Biomolecular Molecular A: Part Acta Spectrochimica treatment. heat upon SiO2, chalcedony, length-fast sedimentary water in of hydroxyl behaviour and the of study near-infrared FT 2018. France. Archaeometry Laugerie-Haute, at of chert site of Solutrean treatment the heat for used technique the Bruxelles Volgu. de iii:Galimard. Digioin: eerhScey oebr21,Boston. 2010, November Society, Research Materials conference, Western International the Mediterranean. in societies Neolithic flint by of used transformations physical the on treatment Pelegrin J. .Colomban a b m o l o C P. , J.-B. , , J.D. A. , , , , , A. , , https://doi.org/10.1111/arcm.12358 P. P. P. J. 1927. 95 rpsd adcuet e pointes des découverte la de propos À 1905. J.-B. L.-B. 9 135–44. 39: ovle rhvsd uémd’histoire Muséum du archives Nouvelles 04.Drcinaddsac nClovis in distance and Direction 2014a. , , 94 érgahee uélge n‘faux un muséologie: et Pétrographie 1984. & 91 xeiet nbfca ok About work. bifacial in Experiments 1981. 4 84–88. 24: .Masse S. .Badou A. ultnd aScééAtrplgqede Anthropologique Société la de Bulletin , .Morala A. , & J. 02 rsalgahcadstructural and Crystallographic 2012. . & rtpbihdoln February 4 online published first , .Aubry T. apéitiedn argo digoinaise région la dans préhistoire La niut ulctosLd 2018 Ltd, Publications Antiquity © , , lnkapr Exchange Flintknappers .Regert M. , .Sciau P. .Torchy L. .Desbrosse R. .Perrenoud C. , .Laurent G. & 9:13–18. 195: & ora fArchaeological of Journal , .Fröhlich F. 08 is nihsinto insights First 2018. . 00 nuneo heat of Influence 2010. . .Pelegrin J. .Walter B. 1 552–59. 81: , , 0–6 Albuquerque: 201–16. : .Roucau C. .Binder D. 225–31. : 07 enouvelles De 2007. . , , lvscce:recent caches: Clovis .Livage J. .Slodczyk A. ce uclou le colloque du Actes 03 Volgu 2013. . 55–57. : , 01 Detailed 2011. . .Desbrosse R. :5–7. 4: , , .Lea V. 145–59. : & , , . , ,

Research Patrick Schmidt et al.

Schmidt, P. , V. Léa, P. Sciau & F. Fröhlich. 2013. Tiffagom, M. 1998. Témoignages d’un traitement Detecting and quantifying heat treatment of ﬂint thermique des feuilles de laurier dans le Solutréen and other silica rocks: a new non-destructive supérieur de la grotte du Parpalló (Gandia, method applied to heat-treated ﬂint from the Espagne). Paléo 10: 147–61. Neolithic Chassey culture, southern France. https://doi.org/10.3406/pal.1998.1134 Archaeometry 55: 794–805. https://doi.org/10.1111/j.1475- 4754.2012.00712.x Smith, P. 1966. Le Solutréen en France.Bordeaux: Delmas. https://doi.org/10.1016/j.jas.2011.09.012

Received: 4 July 2017; Revised: 19 October 2017; Accepted: 21 November 2017

602