II.2 Field Sorting Pottery Groups
p. 24-29
Texte intégral
Purpose of a Field Sorting
1A ceramic pot is a manufactured container used for diverse activities. These include, for instance, storing products in small or large quantities, the transformation of products from one condition to another through cooking for example, or for serving and eating such as containers.
2Besides its practical utility, a pottery vessel also reflects a state of technological development represented by techniques of shaping the vessel, the thickness and hardness of the material, the chosen surface finish, and the decoration (see Section ii.5). This includes traditions concerning style and fashion. Like any other manufactured object, it is not only “just” a technical product but also embodies social and cultural meanings.
3In order to study these aspects, the classification of pottery into a useful analytical corpus during the fieldwork is therefore a major task, representing an essential first step in characterising an ancient society via its material culture.
4The initial sorting of a pottery ensemble into groups is the primary part of the classificatory process and usually takes place in the field where the volume of pottery is the most abundant. Thus, the sorting work needs to be simple and fast and does not usually involve the use of magnification tools or other specialised scientific equipment. Often, primary sorting of a pottery ensemble is undertaken as a practical means of organising the huge, sometimes daunting, range of variation typically exhibited by newly excavated material. Once completed, it allows easier comparison with pottery forms and groups from other archaeological sites and assists the discussion with colleagues about the possible dating and origin of the vessels represented by the potsherds.
Creation of “Field sorting pottery” groups
5The core step is the initial creation of groups into which the material can be sorted. For example, a simple grouping method, based on one or more limited criteria (manufacturing techniques; type of production; supposed function; etc.), can be established as a base. Each group can be defined by a group code such as “Pottery group 1” which, when applied consistently, can be developed further according to the variations in the pottery identified necessitating further groups or sub-groups.
Examples for such groups could be:
6“Pottery group 1”: wheel-made pottery, which can contain open and closed shapes of small to medium sized vessels, such as smaller bowls, cups, dishes or small bottles and jugs, categorised as fine ware used mainly for serving food and/or maybe the preparation thereof, thin-walled with a hard matrix structure using mineral temper, oxidised/reduced and well fired.
Additionally, or subsequently, a sub-group might be added:
7“Pottery group 1.1”: wheel-made pottery, fine ware, including “only” open shapes of small to medium sized vessels such as bowls, cups, small dishes etc.
Another example for a group could be:
8“Pottery group 2”: wheel-made pottery, closed shapes (e.g. jars), coarse ware, used for storageand maybe food preparation, with wallthicknesses from medium to thick, a medium hard to crumbly matrix structure with organic temper inclusions and often an oxidised firing, ranging from well to uneven firing.
A further example could be:
9“Pottery group 3”: hand-made pottery, open shapes such as open pots, deep bowls or large plates, coarse ware, used for cooking and possibly preparation with medium sized wall thickness, rarely thick, crumbly to medium hard structure with organic and mineral temper, and an oxidised uneven firing.
10Often this process is highly influenced by experience, detail, and pragmatism — including the expected volume of material to be classified, the scope and longevity of the project, and even the subject of pre-planned research publications — guiding the ceramic specialists as they create and divide groups and sub-groups during the field season. An average number of 10 to 60 groups is not uncommon, and it happens during the process that the number of groups is either reduced or expanded as initial major groups are defined and later sub-groups required depending on diversity of the pottery ensemble, time restrictions, etc. The fewer and more easily identifiable criteria (or attributes) applied in the beginning as the basis for groups, the faster a large ensemble can be sorted for first results.
The following attribute hierarchy provides a useful example:
11In the form sheet, the fields for “Dating and occurrence”, “Sample reference” (e.g. ID numbers, context numbers or specific areas of the excavation site), “Equivalence with other groups” (internal with personally developed groups or even groups from other excavations), will often be filled in later when a greater amount of data has been processed and major groups formed, as well as the sub-groups expanded or reduced and the acquisition of more clarity relating to certain patterns.
12It is beneficial, if not crucial, to understand manufacturing techniques and the shape of a pottery fragment (a necessary technical aspect required when drawing a conclusion of the vessel’s complete shape from one or several sherds). One should be able to classify, for example, a rim fragment as e.g. a bowl (open vessel) or a bottle (closed vessel).
13The first attribute chosen could be based on observations about possible techniques used by the ancient potters, characterised by the two major traditions of wheel-made pottery, and hand-made pottery. Obviously, allowances must be made for uncertain or hybrid examples, representing composite techniques (See Section ii.5).
14The next step might concern vessel shapes, which can be divided into closed or open forms. The first have relatively small mouth openings, are meant to protect the contents, and include, for instance, large, medium and small jars, bottles, jugs, flasks, etc. Whereas “open vessels”, with a maximum diameter placed near or at the opening, allow easy access to the inside of the container, these include large basins, small and large bowls, cups, beakers and goblets, plates, or platters. Besides these shapes, further pottery forms with a specific function can be noted such as lids, pipes, drains, braziers and libation tables, lamps, miniature vessels, etc.
15Helpful consideration for speeding up the process of the initial classification of an ensemble should be given to the sorting of single sherds into fine wares, utility wares, common wares and coarse wares could be:
Small vessels: those likely to have been used individually, rather than as part of a set or composite vessel. Mainly employed for serving at the table but also for individual activities, thus implying small contents.
Medium sized vessels: those easily carried using one hand, but which content could be shared by several individuals. These vessels were used for multiple purposes, such as storing and transforming products, sharing products during a meal or a meeting, etc.
Large vessels: those which size or weight (especially when full) would have made them difficult to carry using one hand. These vessels were often devoted to storage or to domestic activities on a collective scale, such as cooking for several people, transforming a large quantity of content in the frame of a hand-craft activity.
16This split helps to determine in which group a vessel should be placed based on the ware’s attributes (fine, utility, common and coarse) which can be related to the possible function of a vessel (service, preparation, cooking, storage, etc.). However, combined with information on the paste and structure (e.g. wall thickness, matrix structure and hardness, the use of organic or mineral temper, as well as firing) of the vessel’s ware group, can be a much more defining set of attributes for some ceramic specialists, and given precedence in the hierarchy above size, shape and assumed function. With specific regards to the field sorting process, a pragmatic approach is typically worthwhile, and therefore the order of such attributes within any hierarchy is interchangeable.
17Having defined a certain group, such as our “Pottery group 1” described above, and arranged the relevant sherds accordingly, we are now in a position to sub-divide the group further. Besides the size and function of a pottery vessel, the surface finish and decoration are further attributes of importance.
18Two important categories can be distinguished: those on which a surface finish has been applied and those with a rough or plain surface. The application of a surface finish is often connected to the necessity of waterproofing a vessel or serves a representational, symbolic, or decorative purpose. It can include smoothing, polishing or burnishing, and the application of a slip or wash. Various kinds of decoration, such as incisions, impressions, stamps, or painting, are often incorporated into the finish and can provide further societal, technological, or chronological detail in a classification.
Field sorting groups description form

Persistent identifier: https://doi.org/10.34847/nkl.bfcafy82.
Download (pdf/348 kb): https://api.nakala.fr/data/10.34847/nkl.bfcafy82/735ba38c76e1fb65ab9fc3f184e6a0b9b90bc40b
19“References”, “Equivalence with other groups”, “Dating” and “Occurrence” form the framework for the groups. Within that framework the groups themselves can be classified (rather than the individual sherds). For instance, it may become much clearer that some pottery groups occur more frequently in a specific chronological period and within a certain part of the archaeological site, such as graves or kitchens. The interpretation drawn from that information can again reflect a state of technological development, and additionally might provide an important relative dating tool to date other ensembles.
20Through further study of the material, the focus will inevitably begin to shift from the macroscopic determination of these pottery groups in the field to more detailed and specific analysis. The latter are usually undertaken by specialists, typically concerned with a selected sub-group or “sample” of the total ensemble, providing further details, a more comprehensive analysis of certain components and techniques used to produce the ceramics, and solidify these established field sorted pottery groups (fig. 4).
Figure 4. The various stages of the “field-sorting groups” process

21Additionally, in the creation of these groups, and in providing a comparable and manageable dataset, it is often beneficial to use the created groups for the field counting process as it provides for both a reliable quantification of the ensemble (see Section iii.1) and means to create initial comparable datasets upon which further analyses can be built.
Auteurs
Associated member, Deutsches Archäologisches Institut, Berlin, Germany.
Researcher, CNRS, UMR 5133 Archéorient, Lyon, France.

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