1
METHODOLOGICAL APPROACHES
This chapter is devoted to the description of the excavation methodology and the post-excavation analysis of the contexts and the ceramic finds from House B1, Street 2, and Street 3, to facilitate the understanding of the relation between the ceramic materials and their archaeological contexts.
Excavation at Amheida is based on the stratigraphic method.1 Stratigraphic units have been distinguished according to their formation processes and described either as Deposition Stratigraphic Units (DSU), which are layers or strata, and Feature Stratigraphic Units (FSU), such as floors, walls, pits, ovens, cuts, etc. All the units are identified by a number that is unique within each archaeological area or sub-area.2 Amheida is divided into eleven different “Areas” (Area 1, 2, 3, etc.), each corresponding to a section of the settlement characterized by its location, architectural characteristics, and other notable features. Within each area are sub-areas (sub-area 1.1, 1.2, 2.1, 2.2, etc.) that are generally predefined and recognizable spaces (buildings, streets, etc.). We refer to buildings by using B followed by a number (e.g., B1, B5, etc.), and to streets by using S followed by a number (e.g., S2, S3, etc.).
All finds are recorded daily on Stratigraphic Unit Quantitative (SUQ) data forms. Once a stratigraphic unit is completely excavated, a final SUQ form is filled out to summarize all the daily sheets. The final SUQ is useful, as it gives a general overview of what has been found in each stratigraphic unit. The weight (kg) and the quantity (no.) of all the objects, ceramic fragments, and fabrics are entered into the form, sorted according to the reliability of the archaeological context in which they were found (secure versus insecure contexts).3
All diagnostic and recognizable objects are individually recorded on Find Record forms, where they are identified by an Inventory Code. The Inventory Code consists of the initial of the site (A = Amheida), the year in which the find was recovered, the number of area/sub-area, and the stratigraphic unit from which the artifact came, followed by a unique, progressive number assigned by the recorder (e.g., A07/2.1/243/12054). This form contains the description of the object, the category to which it belongs, the maximum dimensions of the piece expressed in centimeters, the material, the manufacturing technique, and the state of preservation. Each Find Record form is accompanied by a digital color image of the object and in some cases by a drawing in 1:1, 1:2, or 1:5 scale.4
All forms (DSU, FSU, SUQ, and Find Record) are entered into the project’s official online database.5 This important tool allows us to relate every find back to its archaeological context, as well as perform searches and generate statistics.
1.1. QUANTITATIVE ANALYSIS AND CERAMICS PROCESSING
The general methodology applied to the quantification analysis of ceramic materials consists of two main steps. The first takes place in the field and consists of sorting the ceramic fragments found in each stratigraphic unit. Sherds found in secure contexts are divided according to fabrics and wares and are analyzed in detail.6 Each fabric group is weighed, the sherds are counted, and the information is recorded on the SUQ form. Rims, bases, and handles are also counted separately and recorded according to their typology. Body sherds are generally discarded unless they can be re-joined or belong to a stratigraphically relevant unit, in which case all pottery is kept. For non-secure contexts, only diagnostic sherds and body sherds from unknown fabrics or with notable characteristics are recorded on the SUQ form and kept for further studies.
The second step consists of the systematic quantification of the fragments collected for each context and stratigraphic unit, so as to determine the Minimum Number of Individuals (MNI),7 followed by a selection of the most representative shapes and fabrics to establish the main typologies and update the Site Shape Catalogue (SSC), which is the main tool for working in the field. All the diagnostic sherds, i.e., rims, bases, and handles, from each unit are recorded on the Fiche de Comptage where the profile sketch of the sherd is also traced, along with the fabric/ware code and the type number from SSC.8 Unknown fabrics and variants are fully described. The Site Shape Catalogue is built year after year for each excavation area and is intended to collect all the vessel shapes found, to which a code number is given. This system allowed us to avoid drawing all of the diagnostic pieces found in the same area, an efficiency of some importance given the very high number of sherds present at Amheida. Only new types or special cases, as well as complete vessels, are individually documented and described in Find Record forms, with a new Inventory Code assigned to them. These vessels and fragments are drawn,9 photographed, and entered into the SSC with a type progressive number, in order to keep the catalogue constantly updated. The types are arranged in the SSC according to the functional class and shape (bowls, plates, kraters, pots, etc.), and further subdivided according to their morphological parameters (characteristics and diameter of the rim, base, handle, and body).10 The fabric and ware, as well as the manufacturing techniques, also play an important role in classification.
The information comprised in the Find Record form for each type follows the general criteria for cataloguing archaeological finds.11 The surface treatment (slip, pseudo-slip, decorations, etc.), traces of use (e.g., soot), dimensions (diameter of the rim and/or base, wall thickness, height of the vessel), manufacturing techniques (on the wheel, hand-modelled, molded, etc.), and state of preservation (complete, not complete, fragmentary, good, fair, bad) are also indicated.
The macroscopic analysis of the fabric is performed through the use of a monocular magnifying lens.12 This instrument, although far less precise than petrographic and physical-chemical analyses, is a sufficient tool to identify ceramic fabrics directly in the field. The macroscopic study of all ceramic sherds followed these criteria:
• Surface and fracture color of the fabric;
• Hardness;
• Appearance and mineralogical composition of the clay (i.e., color, size, occurrence, and quality of inclusions);
• The final processing (firing modes), surface treatment (i.e., slip, decoration, etc.), and eventual decoration.
In describing a vessel, the color of the fracture is usually provided (i.e., beige, light pink, orange, red, reddish/brown, brown, gray, black, and greenish), as well as the color of the core, if different from the surface (pinkish, reddish; gray, gray/blue). The Nile and ferruginous clays are rich in degreasing (straw, sand, quartz, mica) and melting (limestone, iron oxide, feldspar) additives. Chaff and sand inclusions are present in large quantities, especially in the fabrics characteristic of large storage containers (jars, pithoi) and vessels of domestic use (basins and baking trays). A relevant amount of micaceous inclusions is frequent mainly in the fabrics characteristic of amphorae, in particular in the Late Roman Amphora 7, which typically exhibit grains of mica golden in color and uniformly distributed. The ceramic fabrics in the oasis contain a significant amount of calcareous and iron oxide inclusions. These components result in the vessels presenting surface colors ranging from red-orange to purple, markedly lighter than the traditional productions in Nile clay that are red-brown to brown in color. Medium- to large-sized red and black inclusions are clearly visible in the fracture of vessels produced in calcareous clay, such as jugs and bowls.
The hardness is defined by the vessel’s scratch resistance, determined by the compactness of the clay or by the type and number of particles present inside the fabrics.13 The ceramic body is defined as:
1. Hard or very hard, when scratchable only by a metal tip;
2. Pliable or soft, when scratchable by a fingernail;
3. Brittle, when flakable by finger pressure.
The size of the grain and the amount of inclusions are defined as:
1. Purified — devoid of inclusions visible to the naked eye;
2. Fine — rare, very fine inclusions (0.1–0.2 mm);
3. Medium-fine — contains fine inclusions (0.3–0.4 mm);
4. Medium — medium sized inclusions visible to the naked eye (ca. 0.5 mm);
5.