NEW MYCENAEAN POTTERY PRODUCTION CENTERS FROM THE EAST ERN PART OF CENTRAL GREECE OBTAINED BY NEUTRON ACTIVATION ANALYSIS & & # H Mommsen A Hein D Ittameier J Maran and Ph Dakoronia Institut fur Strahlen und Kernphysik Universitat Bonn Nuallee Bonn & Institut fur Ur und Fruhgeschichte Universitat Heidelb erg Marstallhof th # Heidelb erg and Ephorate of Antiquities Lamia Greece November Abstract Neutron activation analysis results of a set of more than sherds and whole vessels including misred pieces from Lo cris Phthiotis and Southwestern Thessaly are presented The material covers the time p erio d Middle Helladic to Late Helladic I I IC Several new patterns are detected some of which can b e assigned with high probability to that region A sp ecial result concerns several fragments of pictorial craters depicting ships and sea battles found in LHI I IC Middle levels at LivanatesKynos As suggested by our data they originate from a manufacturing place in Eastern Lo cris Introduction Since the midies our archaeometry group is working on a pro ject concerning the classication and provenance determination of Aegean Bronze Age p ottery which has b een a fo cus of archaeological interest for more than a years Of all the dierent p ottery classes used during the Bronze Age sp ecial attention was paid to the ne decorated p ottery of the Greek Mainland and adjacent regions The p erio d of the Late Bronze Age the Mycenaean p erio d is esp ecially well investigated and this for the following reasons Mycenaean decorated p ottery shows a well dened range of vessel shap es and mo tives so that even the smallest fragments can b e attributed with certainty to sp ecic vase types It is very homogeneous in app earance over wide areas and it has a wide dis tribution encompassing almost the whole Mediterranean The archaeological questions arising immediately are How centralized was the pro duction That is to say was this p ottery manufac tured in only a few places and distributed by trade to the dierent regions where it is found to day Or was its pro duction rather decentralized and organized by p otters imitating the shap es and decorations on demand by the customers during this time These questions esp ecially apply to Mycenaean vase painting of the highest quality like the Pictorial Style Was there some sort of internal ranking b etween pro duction places of only regional and such of supraregional imp ortance If this were the cases could it b e that the workshops connected with the Mycenaean palaces esp ecially in the Argolid were the most imp ortant ones To answer these questions by archaeological means tentative assumptions can b e obtained for example by considering distribution patterns of p ottery shap es or styles As is generally agreed to day comp ositional information obtained by natural scientic metho ds will lead to new insights and either corrob orate or contradict these assump tions but also add new questions for example If in addition to a b etween sites comp ositional variation also a variation within a site is detected i e a subgroup pattern can these subgroups stylistically or typologically b e characterized and related to a technological tradition or change Are they related to sp ecic pro duction techniques for dierent customers or use Neutron Activation AnalysisNAA metho d and principles of chemical provenancing To determine the comp osition of p ottery NAA is known to b e esp ecially well suited since its prop erties fulll all the sp ecial demands very well Ab out elemental con centrations p er sample are measured routinely in our lab oratory with the help of an automated sample changer and an elab orate sp ectrum evaluation programMommsen et al and references therein It is a mo died version of the former pro cedure of Berkeley describ ed by Perlman and Asaro Our results can b e directly compared to published Berkeley and Jerusalem data since we calibrated our Bonn standard against the Berkeley p ottery standard Now we have ab out samples of Bronze Age p ottery of Greece in our data bank Some more samples are still awaiting analysis and the work will continue First the principles of ceramic provenancing by elemental analysis will shortly b e summarized p ointing out esp ecially what progresses have b een made in interpretation of the data As long as the clay the raw material for pro duction was not traded the elemental pattern measurable in ceramics is characteristic for a certain production series of a p ottery workshop at a certain place Once this pattern is known e g by measuring socalled reference material that is material which is pro duced lo cally with a high probability all pieces of unknown pro duction place having this elemental pattern can b e assigned to that origin As members of a pro duction series we dene simply all pieces which analyse the same This is a reductionist approach as Pollard and Heron wrote p but it has the advantage that it is free of any p ossibly misleading interpretations and if used as a rst working hypothesis results in given facts esp ecially if stringent rules for chemical similarity are applied This similarity in many elemental concentrations is an indication that the ancient p otters did not change anything during the manufac turing pro cess or at least to b e precise that no change o ccurred which inuenced the concentrations of the elements measured If a new clay or clay mixture was used or if a new clay renement technique was applied a new pattern of elemental values may show up a second pattern p ointing also to this pro duction place is pro duced Thus there may b e many dierent patterns for each pro duction place Therefore the nding of a dierent pattern in p ottery from the same site do es not necessarily mean that we are dealing with pro ducts pro duced somewhere else we might have found just a second pro duction series at the same place This is often exp erienced if material of dierent type is analysed which was manufactured probably on purp ose with a dierent recip e For instance in Roman vessels pro duced contemporaneously ab out years ago in the same p ottery workshop in Bonn we detected dierent patternsMommsen et al o ccurring in dierent vessel types We b elieve that the ancient p otters of that workshop in Bonn used dierent recip es in the pro duction of these vessels they already optimized their pro cedures to satisfy quality or market demands But with certainty b oth patterns are characteristic for the pro duction in Bonn One of the main problems in provenancing p ottery is the availability of reference material since for these control samples the pro duction place has to b e known b efore hand Rather secure are kiln wasters found in the vicinity of a p otters kiln But during the Mycenaean p erio d only very few p otters kilns have b een detected on the Greek Mainland and these kilns only rarely yielded misred pieces In such a situation one has to rely on archaeological results which might introduce a bias from the b eginning Therefore only the analysis of a very large number of samples will allow reaching well founded conclusions Imp ortance of precision of measurement and b est relative t Another crucial p oint in provenancing is the quality of the measurements p erformed In order to classify p ottery by its elemental comp osition as many elements as p ossible have to b e measured with a high precision which is a dicult task for trace elements That go o d measurements with high precision are needed is not astonishing since all ceramic material contains more or less similar elemental abundances We will demonstrate this on a newly detected group of sherds representing a pro duction series from a p ottery workshop or district probably in Eastern Lo cris and quite p ossibly even in the coastal settlement mound called Pyrgos Livanates which can b e identied with Kynos according to Homer the home of Ajax Dakoronia a The group contains to o all the samples from pictorial craters depicting Mycenaean war ships see b elow In Tab the average concentrations M in p ercent or ppm are listed together with the spreads sigma ro ot mean square deviations The third column expresses the spreads in p ercent of the average values As can b e seen for many elements spreads of less than are obtained As example for an element measured with such a precision Fig shows the single raw data of La for the sherds of this group Per denition ab out of all the values lie inside a range of M sigma There is only one outlying sample which for now is assigned to this group b ecause all the other elemental values t but may b e found to b e a member of a subgroup if more samples are analysed The discrimination can b e brought into still a b etter fo cus by a b est relative t of the data This is similar to the consideration of elemental concentration ratios instead of the concentrations directly and corresp onds to the reduction of the degrees of freedom by which is not harmful b ecause of the many elements measured The eect of such a b est relative t to the data of the group Lo crisl is shown in the following columns of Tab and for the element La in Fig The average values M are more or less unchanged but the spread values decreased enhancing the p ossibilities of discrimination The reason for this is that on the one hand all exp erimental errors lowering or raising all the values by constant amounts due for example to weighing errors or to neutron ux inhomogeneities cancel and that on the other hand dilution eects of the clays by additions of slightly varying amount of