NOTES ON GAULISH SAMIAN POTTERY AND ITS ANALYSIS BY NEUTRON ACTIVATION

BY GRACE SIMPSON, Lady Margaret Hall

INTROIXJCTORY NOTE: Suniian pottery was good quality mawproduced table- wure made in Roman Guul from about the beginning of the Christiun cru.

T HE purpose of the neutron activation analysis of potsherds is to give a partial chemical analysis to help to determine their places of origin which cannot. for various reasons. be discovered by normal archaeological methods.

Samian ware or terra sigilhra was chosen as a medium for demonstrating the technique because many of the sites of ancient manufacture are known. and most samian vessels or fragments from vessels can be attributed to their place of origin and often can be identified as the work of an individual potter. Some of the decorated bowls can be dated, by stratification and site distribution, to within twenty or thirty years, the working life of a potter. Therefore samign pottery seemed to be a suitable medium for demonstrating the technique; a good deal of archaeological information was known about each of the sherds sampled for analysis; and thus there was an independent means of assessing the results obtained by neutron activation.

The archaeological methods of study employed are the classification of potters' names and marks and the great variety of styles of decoration, and the typology of the various forms of vessels. for certain forms were modified during a century or more of manufacture and others were in time replaced by different, usually simpler, forms which were cheaper to produce. Gaulish samian ware was manufactured on a very large scale. Accounts written on platters and then baked, found at La Graufesenque in South Gaul, list in several cases between 20-30,OOO vessels, although it is not known whether each records the produce of one workshop during a period or perhaps represents a consignment for export ordered by one merchant. Vast quantities of Gaulish samian have been found in the provinces of the western Roman Empire, including Britain.

The places of manufacture in western Europe, about thirty in number, were active at different periods from the early first century A.D. to the middle of the third century when the latest factories were destroyed by the barbarian invasions. Within those two and a half centuries at any particular time some factories were active, some had ceased production, and others had not yet begun; for example, early in the second century exports from South Gaul had ceased, Lezoux. Martres de Veyre and Chemery were active. and most of the East Gaulish factories had not started production. These differences in period are not evident in the results of the analysis which, however, gives us information which could not be obtained by archaeological methods. and these will now be described.

The samples chosen for analysis came from factories in regions as far apart as Italy, South. Central and East Gaul, and Britain, and the first objective was to discover if the technique could distinguish these geographical differences. It should be noted that the clays used at all these centres of manufacture look remarkably alike. There are very slight differences in colour between certain factories, but as a whole samian pottery consists of a fine hard clay body, pinkish-red in colour. covered by a glossy red slip. Colour and general appearance therefore are not helpful guides to origin, and it was hoped that neutron activation would reveal the

A R C H A E O M E T R Y 21

presence in the clay bodies of elements in quantities which varied between one factory and another.

Secondly, amongst the samples, three factories were represented respectively by three bowls made by one individual; three by the potter SATTO at Chdmery, three by the Small S Potter at Martres de Veyre, and three by the Aldgate Potter who probably worked in Britain. The objective here was to test the consistency of the clay used by one potter working in one locality: the supposed consistency of each potter’s clay was confirmed by the analysis as is shown in Table I of Miss Emeleus’ article.

The origin of some samian potsherds cannot be determined by archaeological methods either because they are too small or because they have unusual form:, of decoration and do not conform to any classification. Therefore samples of samian vessels of unknown or uncertain origin were included in the hope that clue’s to their origin would be forthcoming. and very interesting results have been obtained.

RESULTS: Miss Emeleus, as she describes, measured a ‘peak intensity’ for the common

elements manganese and sodium on the same principles with the analysis carried out at Brookhaven National Laboratory in the United States’. Miss Emeleus found that the samples fell into five groups; and it will be noticed that the places where the sherds were found are not significant, for sherds found at Corbridge in Northumber- land fell into Groups 2, 3 and 4.

Group Code 1 SA I

I1 111

2 c 1-111

3 D 1-111

R 1-111 B 1-111

a IV-VI 4 G 1-111

La I-In

T 1-111 M I-III L I

III BL I

11.n1 BW I CI I-111 AP 1.n m

5 L n

Potter’s Name CAMVRI cv SATTO -

- Small S Potter PATERNVS CINNAMVS (black slip) .. *. - - Aldgate Potter

BA&S ’*

Site of Fbtsherd manufacture found in in Italy Rome

CMmery. Corbridge

La Madeleine, Corbridge

Rheinzabern London, etc. Blickweiler, Corbridge

Colchester Colchester La Graufesenquc, London, etc.

Lavoye Corbridge

Trier (E. Gaul) Corbridge Martres de Veyre Corbridge Laoux (C. Gaul) London

L U O U X CatLerick Alchestcr

unknown Colchester Colchester Colchester uncertain Chichester

London ? (id’Chtral Gaul) London

nr. Nancy

nr. Nancy

nr. Saarbriicken

nr. Rodez (S. Gaul)

@ept. Meuse)

22 A R C H A E O M E T R Y

A R C H A E O M E T R Y 23

GROUP 1 consists of three sherds of Italian Sigillata. all found at Rome, but not necessarily all made at the same place in Italy. They have similar values and are distinctly different from the other groups.

GROUP 2 consists of three sherds by SATTO who worked at Chemery between Nancy and Metz (we MAP). Chgniery is not far from factories in group 3 and 4. but it appears that the clay used by SATTO can be distinguished from other Gaulish samian clays. This is interesting in itself. and also because a Central Gaulish potter. the Potter of the Hoxttz. appears to have worked also at ChCniery in East Gaul where a mould and nunierous bowls in his style have been foundz. His products could be analysed to learn whether in fact some are made with clay from Chemery. I am not suggesting that such an experiment is necessary, but it is an instance of how the technique or some other form of analysis could increase archaeological knowledge.

GRorlP 3 comprises three Last Giulish factories between the Moselle and the Rhine. La Madeleine. Rheinzahern and Blickweiler. It also includes three samples from the Colchester saniian kiln (CI IV-VI). The other samples from the Colchester kiln fall into Group 4 (CI I-111).

GROUP 4 includes factories in South, Central and East Gaul, far apart in time and place, but related geographically because all are situated t o the west of the Rhone and Moselle valleys. Trier is in Group 4, and Trier lies in the Moselle valley: the question arises, was the deposit of Trier samian clay west of the valley. as the analysis sugests? Two factories in Central Gaul are reprexnted. Martres de Veyre near Clerniond Ferrand, and Lezoux near Vichy. Red and black slip vessels from Lezoux were included. The black slip vases are uncommon and were made by firing in a reducing kiln". The common red samian from L~zoux was represented by samples from decorated bowls by PATERNVS, BANVVS and CINNAMVS respectively. The BANVVS sherd proved to be markedly different from the other two and is solitary in Group S i 3 u t the values of I . I and I l l and HL. I- 111 are similar.

The cup BW in Group 4 has a black slip and unusual form and decoration. It was found at Colchester but presumably was made somewhere on the Continent3. I t has manganese and sodium values similar to the black Central Gaulish vases, but this does not necessarily imply the same place of manufacture.

At Colchester, samian pottery was made for a local market and the period of production seems t o have been short. No suitable natural deposits of samian clay are yet known in Britain4. I f the clay was imported from Gaul the costs involved might partly explain the lack of success in the venture and also why three of the samples fell into Group 3 and three into Group 4. This matter would repay further attention, perhaps after the area of the Colchester samian kiln has been fully excavated.

It is possible that the Aldgate Potter made samian ware in Britain either in London where an unusuable kiln-waster has been found, or at a villa near Pul- borough in Sussex where there were fragments from moulds in his distinctive stylp. The Aldgate Potter learned his trade from Central Gaulish potters, and it is interest- ing that the neutron activation analysis groups his products with the Central Gaulish wares and also with the samples c1 1-111 from the Colchester kiln,

The sherds from which the black samples were taken were illustrated by the writer in The Antiquaries Journal, xxxvii, 1957. pp. 29-42, NOS. 6, 21. 28%

24 A R C H A E O M E T Y Y

IN GROUP 5 is the sherd L 11 in the style of BANVVS of Central Gaul. He worked at Lezoux where a number of his moulds have been found, and it has also been supposed that he worked at Lubik not far away. Many of his bowls were found at Lubik in 1878-9 but no moulds are recorded there6. Other potters can be shown to have worked at more than one place, however, and the marked difference between the values of his sherd L I1 and those of PATERNVS and CINNAMVS raises the questions. was L 11 made at Lubik, and are its values similar to the samian clay of Lubie? In order to decide one way or another it would be necessary to analyse a number of vessels from both places.

The several interpretations I have suggested on the basis of the analysis are not conclusive, but they provide useful data which could be studied profitably in more detail, possibly by other means than the expensive method of neutron activation analysis. It is clear that the technique has grouped the samples in a manner that is understandable both geographically and archaeologically. Furthermore, the results obtained refer to the places of manufacture, and not to the places where the sherds were found. This holds promise for archaeologists who excavate or study Gaulish samian pottery, because sometimes it is impossible to determine the origin and therefore the date of a broken or defaced potsherd found in a stratified or otherwise important context7. Much time and trouble could be saved if. by analysis, such a sherd could be shown to fall within a particular group; and to do this effectively some means of distinguishing between first-century South Gaulish and second- century Central Gaulish pottery, both in Group 4. is required.

Thanks are due to the authorities of the British Museum, the Ashmolean Museum, the Colchester and Essex Museum, and the Corstopitum Museum for allowing samples to be taken. The other samples were supplied by the writer.

REFERENCES 1. E. V. Sayre, A. Murrenhhoff, & C. F. Weick. T h e Nondesrrurrive Analysis of Ancienr

Porsherds rhrough Neurron Acfwafion, Brookhaven, April, 1958). (BN.L. 508 p-1221).

no. 1857. See also J . A. Stanfield & Grace Simpson Cenrrd Guulish Porters (Oxford, 1958). p. 27.

2. E. Delort, Vases O r n b de l a Mose I le (Nancy, 1953), pp. 219-21, modble 610. and pl. 81.

3. 4. 5. Grace Simpson, lournd of Roman Studies, xlii, 19!2. 68-71. 6. 7.

The Anriquaries Journal, xxxvii, 1957, p. 42 and pl. xiii, no. 35. M. Bimson, The Anriquaries Journal, xxxvi, 1956.

J . Mchelette, Les Vases C?rmniques OrnPs de la Gaulc Romaine (Paris, 1904). 1, p. 158. Similarly, concerning Arretine ware, see H. Comfort in Archaeologiral Discoveries in

202, n. 5.

Sourh Arabia by R. L. Bowen Jr. er al. (Baltimore 1958, p. I99 No. 3).