aRchaeometRIc anaLyses of hattIan and
hIttIte metaLwoRk
thomas ZImmeRmann1
AbstrAct
In this paper, I will discuss recent quantitative X-Ray Fluorescence analyses on 3rd and 2nd millennium BC metal objects from central Anatolia. I will
discuss phenomena such as high tin values attested in some copper-based artefacts and a growing corpus of copper-silver alloys, which represent a still exotic but persistently growing facet of Early Bronze Age alloying techniques. Finally, the archaeometric data retrieved from the ‘Bronze tablet’ of Hattusa is here added to the still meagre collection of scientifically analysed Hittite metalwork.
anatolia proper, the vast and resourceful landscape of central turkey, has long proven to be a fascinating arena for the exploration of early advances in metal production and consumption. the splendid metal assemblages recovered from sites such as troy, alaca höyük or eskiyapar have yielded evidence for very advanced alloying and ornamentation techniques. anatolia, thus, evolved from the proverbial ‘cradle of castings’ (hence the book title of Bilgi 2004) to a ‘college of castings’ in the later 3rd millennium Bc. our knowledge of these advanced alloying techniques and casting procedures as well as the origin of the raw materials involved, are due, in addition to more traditional archaeological evaluations of these materials and their much debated cultural affiliations (cf. Börker-klähn and krafzik 1986: 55-57; korfmann 1986; and akurgal 1989; also Zimmermann 2006-2007 for an overview), to archaeometallurgial studies, starting as early as the late 19th century.
archaeometallurgical studies of material from the north-western fringes of modern Turkey, specifically from Troy and its immediate vicinity, have explored a wide array of research questions ranging from technological issues to provenance and raw material sources (pernicka et al. 1984; pernicka et al. 2003; Begemann, schmitt-strecker and pernicka 2003). By way of contrast, archaeometric approaches to pre-classical central anatolian materials seem to have lost their momentum following initial contributions by Przeworski (1939) and Koşay (1938), and more comprehensive studies by Esin (1969) and de Jesus (1980). In recent years, research has focused primarily on the
1 phd, assistant professor, Bilkent university, department of archaeology, 06800 Bilkent-ankara, turkey, e-mail: zimmer@bilkent.edu.tr
detection and chemical characterisation of raw material sources and the question of their exploitation in prehistoric times (Wagner and Öztunalı 2000; Wagner et al. 2003).
While such provenance work has been of great value for the wider field of archaemetallurgical studies, the existing and growing corpus of 3rd millennium Bc metal artefacts from central anatolia is in dire need of re-examination. there are two compelling reasons for such an endeavour: the first is the scarcity, or even complete absence, of archaemetric data for metal artefacts from the periphery of early ‘centres’ such as alaca höyük; the second, is the enormous discrepancy in analytical results between older and more recently analysed artefacts of similar date and spatial distribution (for an example see results from tarsus-Gözlükule in Özbal and Kuruçayırlı 2005).
In 2005 initial steps were taken towards implementing a programme to reappraise central anatolian metalwork of the 3rd millennium Bc, a period of social innovation and ever-growing interregional contacts. the result was the initiation in the following year of a joint research project bringing together specialists from the turkish atomic energy authority – sarayköy nuclear Research and training centre (sanaem), Bilkent university department of archaeology, ankara university department of protohistory and near eastern archaeology, and the ankara museum of anatolian civilizations.
In 2006 and 2007, a series of complete or well preserved artefacts, mostly from the Early Bronze Age (thereafter EBA) cemetery of Resuloğlu, were selected for initial non-destructive analysis using a portable XRf-device, while heavily fragmented items from the same location, and occasionally even the same object, were selected for destructive analysis at the sanaem laboratories. the results showed an interesting tendency for unusually high tin values (up to almost 17 weight %) in copper-based items (Zimmermann 2007; Zimmermann and Yıldırım 2008). Such high tin values cannot be explained by past attempts to enhance the mechanical quality of the finished object. An average of 3-5 weight % is generally considered to be more than sufficient to produce bronze with adequate strength and durability (pernicka 1990, 47-56). as already suggested in previous publications (Zimmermann 2007; Zimmermann and Yıldırım 2008), the addition of an alloying agent such as tin in very high quantities may have been intended to produce a subtle colour change in the finished product. alternatively, the extravagant and technologically unnecessary use of rare or costly materials may reflect an underlying sense of economic lavishness (conspicuous consumption) (Zimmermann 2009). either way, the over-use or conspicuous consumption of a much sought after alloying agent such as tin, does at least testify to a secure supply of this raw material and its liberal use in objects found and perhaps also made at small, rural settlements in the wider periphery of early centres such as alaca höyük or eskiyapar.
the results also show a considerable variety in selection and quantity of copper-based alloys, ranging from unalloyed copper to ‘classic’ bronze, arsenic copper and
lead copper mixtures. an item of particular note is a pin with a ratio of about 3 weight % of antimony, another is a plain, copper-based macehead with an average of 18.4 % antimony, a rather rare component in artefacts from the central anatolian Bronze age (figs 1 and 3). of even greater importance is the growing number of copper-silver alloys identified amongst the funerary offerings from undisturbed burial contexts at Resuloğlu. For example, a silver-based hair-ring proved to be alloyed with substantial percentages of both gold and copper, while a second silver-based pin proved to be alloyed with a substantial percentage of copper, but in this case, showed no traces of gold (figs 2 and 4).
Copper was the main raw material for two other items of jewellery from Resuloğlu, a hair- or lock-ring, and a torque, both of which were alloyed with high amounts of silver (8 and 15% respectively). artefacts made of this rather exotic copper-silver alloy to date have only been attested in larger numbers at one other findspot: the ‘Royal Burial’ from arslantepe dated to c. 3000 Bc (frangipane 2001; hauptmann et
al. 2002). the grave produced several jewellery pieces and also a dagger (hauptmann et al. 2002: 51 table 7) made of this extraordinary combination of metals. for the rest
of anatolia, evidence for such an alloying procedure is rather meagre. silver ingots from mahmatlar contained up to 3% copper, but it was probably added to increase their weight and size. the same may also be true of a fragment of silver from middle Bronze age contexts at acemhöyük, with approximately 2 weight % of copper, and the same perhaps applies to several copper-silver objects from an early 3rd millennium Bc workshop at Çukuriçi höyük near ephesos.2
outside of anatolia, several Bronze age and later artefacts made from copper-silver alloys are attested in mesopotamia (see charts in hauptmann and pernicka 2004). to the north and northwest, evidence for this alloying procedure comes in the form of copper-silver rings from domestic contexts at the middle Bronze age sites of arich (armenia) and modinache, satchkere (Georgia), along with four kozarac-type axes whose origin is unknown but likely to have been in the carpathian basin (hauptmann et al. 2002: 57). at present, this very limited data set does not permit us to trace the origin(s) of this alloying procedure; and perhaps there was no single origin, as these unusual alloys could have been accidentally created, the results of unsophisticated recycling of scrap metal for instance. however, this is unlikely in the case of the material from the arslantepe ‘Royal Burial’.
from the above discussion and the intriguing results of archaeometric studies it is evident that more such analyses have to be carried out on metalwork from sites of the central anatolian Bronze age. Indeed, the success of the 2006 and 2007 research programme prompted further work in 2009 on other EBA metal artefacts at the Çankırı museum. In this season, we were also able to extend our research programme to include an artefact of hittite date. after all, there is an even greater need for a full-scale programme of archaeometric research on materials from this period. here we have
2 I am indebted to dr. Barbara horejs, austrian archaeological Institute, for this information prior to formal publication of the material.
on the one hand a rich and comparatively well-studied body of textual evidence for metals and their profane and ritual application in hittite times (kempinski and košak 1977; floreano 2001; siegelova 2008) and on the other, a ridiculously small corpus of archaeometric data for the same period (Bachmann 1984). the question whether hittite metalwork continued earlier ‘hattian’ traditions or represents completely new and innovative ways in the production and consumption of metals, thus, remains unanswerable at present. the one item of apparent hittite date, which we examined at the Çankırı museum, a metal axe of unknown origin but distinctively Hittite in shape, produced results of some interest: the copper based artefact had a rather high tin content (11.8 weight % average), along with some traces of arsenic. not only does this measurement add another analytical result to the still meagre portfolio of archaeometric studies of 2nd millennium Bc central anatolian artefacts, but the use of a higher percentage of tin as an alloying agent ties it to pre-hittite central anatolian alloying traditions (Zimmermann et al. 2010: 227).
the success of our research programme directly led to the extraordinary opportunity to carry out quantitative non-destructive XRf-analysis on one of the most prominent metal items from the later part of the hittite empire period, the inscribed metal tablet commonly known as the ‘kurunta treaty’ or simply the ‘Bronze tablet’ (Zimmermann
et al. 2010). the opportunity came when this unique artefact, which is on display in
the museum of anatolian civilizations in ankara, was re-housed in a new display case. four areas of the tablet with little or no traces of patina were scanned, and all four yielded astonishingly high values of tin, up to 38 (!) weight %.
this enormous quantity of tin, far more than what is necessary to achieve high-quality bronze, must have been added to alter the final colour of the object, giving it a silverish lustre. the peltier-cooled pIn detector of our p-XRf device will penetrate only a few microns into the surface of an artefact, and so it is possible that only a thin coat of tin was applied to the tablet’s surface to make it seem as if it were entirely made of silver. this hypothesis would tie in nicely with the results of a recent philological study of the hittite word for tin, ‘arzili-‘, which revealed that objects of religious or other ritual significance such as statues and water basins were covered with a layer of tin (soysal 2006: 111-112). It is entirely possible that an object such as the ‘kurunta treaty’, which contained a political agreement of utmost importance to the hittite state and in this way was also of ritual value, may have been treated in the same manner.
to conclude, despite the to date rather limited number of artefacts from eBa sites in central anatolia, and an even smaller number of objects dating to the 2nd millennium Bc, the results presented in this paper clearly demonstrate the great potential of archaeometric studies. one can only hope for a systematic revival of metallographical studies using the much more accurate, and in some cases portable, instruments now available. only through such a revival and the analysis of the rich metal collections in museum stores and displays from old and recent excavations can we further unveil the technological dimensions of eBa and hittite metal production and consumption.
through a more frequent and systematic use of appropriate instruments, their glow may shed a bright light onto the mysteries of early metal alloying in anatolia.
Acknowledgements
I want to express my deepest gratitude to my esteemed colleagues Tayfun Yıldırım (ankara university), Latif Özen (museum of anatolian civilizations ankara), Abdullah Zararsız and Yakup Kalaycı (both SANAEM) for their continuous support and expertise. I am likewise indebted to Barbara helwing for fruitful discussions, and Julian Bennett for proofreading the english manuscript.
Bibliography
akurgal, e.
1989 are the ritual standards of alacahöyük royal symbols of the hattian or the hittite kings?: in k. emre, m. mellink, B. hrouda,n. Özgüç (eds), Anatolia
and the Ancient Near East. Studies in Honour of Tahsin Özgüç, ankara,
1-2. Bachmann, G.
1984 düsenrohre und Gebläsetöpfe: keramikfunde aus metallverarbeitungs-werkstätten: in k. Bittel (ed), Boğazköy VI. Funde aus den Grabungen bis
1979, Berlin, 107-115.
Bilgi, Ö.
2004 Anadolu. Dökümün Beşiği. Anatolia. Cradle of Castings, Istanbul.
Börker-klähn, J., krafzik, u.
1986 Zur Bedeutung der aufsätze aus alaca höyük: in Die Welt des Orients 17, pp. 47-60.
de Jesus, p.
1980 The Development of Prehistoric Mining and Metallurgy in Anatolia. BaR
International series 74, oxford. esin, u.
1969 Kuantatif spektral analiz yardımıyla Anadolu’da başlangıcından Asur kolonileri çağına kadar Bakır ve Tunç madenciliği, Istanbul.
floreano, e.
2001 the role of silver in the domestic economic system of the hittite empire: in
frangipane, m.
2001 the transition between two opposing forms of power at aslantepe (malatya) at the beginning of the 3rd millennium B.c.: in TÜBA-AR 4, pp. 1-24. hauptmann, a., schmitt-strecker, s., Begemann, f., palmeri, a.
2002 chemical composition and lead isotopy of metal objects from the “royal” tomb and other related finds at Arslantepe, eastern Anatolia: in Paléorient 28/2, pp. 43-69.
hauptmann, h., pernicka, e. (eds)
2004 Die Metallindustrie Mesopotamiens von den Anfängen bis zum 2. Jahrtausend, Rahden/westf.
kempinski, a., košak, s.
1977 hittite metal ‘inventories’ and their ecomonic implications: in Tel Aviv 4, pp. 87-93.
korfmann, m.
1986 die ‘große Göttin’ in alaca höyük: in IX. Türk Tarih Kongresi Ankara:
21-25 Eylül 1981, pp. 153-163.
Koşay, H. Z.
1938 Alaca Höyük Hafriyatı. 1936 daki çalışmalara ve keşiflere ait ilk rapor,
ankara. Özbal, H., Kuruçayırlı, E.
2005 New metal analysis from Tarsus-Gözlükule: in Ü. Yalçın (ed.), Anatolian
Metal III, Bochum, 49-61.
pernicka, e.
1990 Gewinnung und Verbreitung der metalle in prähistorischer Zeit: in Jahrbuch
des Römisch-Germanischen Zentralmuseums Mainz 37, pp. 21-129.
pernicka, e., seelinger, t. c., wagner, G. a., Begemann, f., schmitt-strecker, s., Eibner, C., Öztunalı, Ö., Baranyi, I.
1984 archäometallurgische untersuchungen in nordwestanatolien: in Jahrbuch
des Römisch Germanischen Zentralmuseums Mainz 31, pp. 533-599.
Pernicka, E., Eibner, C., Öztunalı, Ö., Wagner, G. A.
2003 early Bronze age metallurgy in the north-east aegean: in a. wagner, e. pernicka, h.-p. uerpmann (eds), Troia and the Troad. Scientific Approaches, Berlin-heidelberg-new york, 143-172.
przeworski, s.
1939 Die Metallindustrie Anatoliens in der Zeit von 1.500 bis 700 v. Chr. – Rohstoffe, Technik, Produktion, Leiden.
siegelova, J.
2008 Metals in Hittite records: in Ü. Yalçın, H. Özbal, A.G. Paşamehmetoğlu (eds),
Ancient Mining and Metallurgy in Turkey and the Eastern Mediterranean,
soysal, o.
2006 das hethitische wort für ‘Zinn’: in Historische Sprachforschung 119, pp. 109-116.
Wagner, G. A., Öztunalı, Ö.
2000 Prehistoric copper sources in Turkey: in Ü. Yalçın (ed.), Anatolian Metal I, Bochum, 31-67.
Wagner, G. A., Wagner, I., Öztunalı, Ö., Schmitt-Strecker, S., Begemann, F.
2003 archäometallurgischer Bericht über feldforschungen in anatolien und bleiisotopische studien an erzen und schlacken: in t. stöllner, G. körlin, G. steffens, J. cierny (eds), Man and Mining – Mensch und Bergbau. Studies
in Honour of Gerd Weisgerber on Occasion of His 65th Birthday, Bochum,
475-494. Zimmermann, t.
2006-7 symbols of salvation? – function, semantics and social context of early Bronze age ritual equipment from central anatolia: in ANODOS – Studies
of the Ancient World 5-6, pp. 509-520.
2007 anatolia as a bridge from north to south? – Recent research in the hatti heartland: in Anatolian Studies 57, pp. 65-75.
2009 excavating thorstein Veblen – thoughts on conspicuous consumption amongst social elites in early Bronze age asia minor: in Ç. Özkan aygün (ed.), SOMA 2007. Proceedings of the XI Symposium on Mediterranean
Archaeology, Istanbul Technical University, 24-29 April 2007. BaR
International series 1900, oxford, 463-466. Zimmermann, T., Yıldırım, T.
2008 three best to have in plenty – Rethinking central anatolian early Bronze Age alloying traditions: in Ü. Yalçın, H. Özbal, A. G. Paşamehmetoğlu (eds), Ancient Mining in Turkey and the Eastern Mediterranean, ankara, 87-97.
Zimmermann, T., Özen, L., Kalaycı, Y., Akdoğan, R.
2010 The metal tablet from Boğazköy-Hattuša: first archaeometric impressions: in Journal of Near Eastern Studies 69, pp. 225-229.
Inv.No. Item Cu Ag Pb Fe As Sn Sb 10-10-2003 Pin 94,5 - 0,3 1,8 3,1 - -10-27-2003İ Pin 97,4 - - 0,7 - 1,4 -10-19-2003 Bracelet 97,8 - 0,1 0,4 1,7 - -10-20-2003 Bracelet 98,0 - - 0,4 0,5 1,0 -10-04-2003 Pin 93,8 - 0,2 - 0,5 5,5 -6-1-2004 Dagger 93,2 - - 0,3 6,6 - -6-6-2004 Dagger 97 - - 0,1 3,0 - -6-8-2004 Pin 93,5 - 0,3 1,0 5,2 - -6-12-2004 Pin 95,8 - - - 0,5 3,8 -6-13-2004 Torque 98,6 - - 0,4 - 0,8 -6-19-2004 Pin 95,2 - 0,3 0,1 - 4,4 -6-18-2004 Pin 93,1 - - - 0,2 6,9 -6-24-2004 Pin 93,9 - 0,1 0,2 0,3 5,7 -6-25-2004 Torque 88,5 - - - 0,2 11,2 -6-26-2004 Pin 91,9 - 0,7 0,2 0,4 7,1 -6-28-2004 Pin 96,5 - - 0,2 - 3,3 -8-9-2005 Pin 95,5 - 0,2 - - 4,2 -8-21-2005 Pin 92 - - - - 8,0 -8-25-2005 Anklet 86,1 - 11,4 0,1 0,3 6,1 -9-29-2005 Torque 88,7 8,49 - 0,4 2,4 - -8-32-2005 Lockring 83,8 15,2 - 0,8 0,1 - -9-8-2006 Pin 95,2 - 0,3 0,1 2,4 - 2,6 9-17-2006 Macehead 80,3 - 0,2 - 1,2 - 18,1
9-26-2006a Jug (Body) 96,7 - 1,0 - - 2,3
-9-26-2006b Jug (Handle) 96,3 - 1,4 - - 2,3
-18-3-2007 Pin 81,9 - 14,5 - - 3,4
-18-4-2007 Pin 98,5 - - - 1,5 -
-18-25-2007 Pin 92,2 - 2,8 - 1,2 3,1
-18-26-2007a Pin (Body) 88,6 - 2,9 - 0,6 8,0
-18-26-2007b Pin (Head) 89,4 - 6,7 - - 3,7
-14-3-2008 Pin 98,6 - - 0,18 0,2 1,1
-14-1-2008 Pin 94,7 - 0,5 0,42 4,4 -
-14-2-2008 Pin 93,6 - - 0,69 5,7 -
-8-30-2005 Dagger 94,3 - - - 0,1 13,5
-fig. 1: XRf analysis chart of selected items from the early Bronze age necropolis of Resuloğlu.
No Item Cu Ag Pb Fe As Sn Au 1 pendant 0,6 12,6 - 0,4 - - 85,4 2 pendant 2,0 12 - - - - 86,0 3 hairring 15,0 84,3 0,2 0,5 - - -4 hairring 85,0 50 - - - - 24,0 5 hairring 83,8 15,3 - 0,8 - - -6 torque 88,7 8,5 - 0,4 2,7 - -fig. 2: analysis chart showing early Bonze age cu-ag, ag-au and Cu-Ag-Au alloys from Resuloğlu.
Fig. 3: Copper-Antimony macehead from Resuloğlu.
