Archaeological Ceramic Materials

The text which follows is based largely on the personal experience of the authors. The examples used which concern archaeological material, thin sections of sherds and many of the case studies are for the most part those which we have developed ourselves. This experience. may seem biased when one thinks of the large experience of petrographic archaeology, and this is surely true, but it is a reflection of our observations which are more complete for the objectives we have in mind than most of the examples given in the literature. For example, we have access to initial sherds, photo graphs, grain-size measurements and so forth for the same materials and we can present a specific archaeological context and problem using these data. Of course, there have been many studies on the same general subjects published elsewhere. As it turns out, our collective experience covers two of the major fields of investigation, the old (European) world and the new (American) one. It is evident that the problems are different in these two worlds. The contexts of production, distribution and use are different. The evolution of tech niques is very different although covering similar time periods. These two view points are complementary and, we hope, will enrich the investigative methods and outlook of workers in both cultural areas.

Practical approach in the study of ceramics Clearly targeted for non-specialists (archaeologists, geologists)

Inhalt
1 Introduction.- 1.1 Objectives.- 1.2 Methods.- 1.3 Vocabulary.- 1.4 Structure of the Book.- 2 Rocks and Minerals.- 2.1 Chemical Elements and Their Chemical Affinities.- 2.2 Major Rock Types.- 2.3 Minerals.- 2.3.1 Mineral Formulae.- 2.3.2 Major Mineral Families.- 2.3.2.1 Silicates.- 2.3.2.1.1 The Silica Minerals and Quartz.- 2.3.2.1.2 Feldspars.- 2.3.2.1.3 Pyroxenes and Amphiboles.- 2.3.2.1.4 Olivine.- 2.3.2.1.5 Micas and Chlorite.- 2.3.2.2 Carbonates.- 2.3.2.3 Oxides.- 2.3.3 Mineral Grain Shapes.- 2.4 Minerals in Rocks.- 2.4.1 Sedimentary Rocks.- 2.4.2 Igneous Rocks.- 2.4.3. Metamorphic Rocks.- 2.4.3.1 Metamorphic Pelites.- 2.4.3.2 Metamorphosed Carbonates.- 2.4.3.3 Metamorphosed Igneous Rocks.- 3 Clay Minerals and Their Properties.- 3.1 Introduction.- 3.2 Chemical Constitution of Clay Minerals and Clay Mineral Families.- 3.2.1 Mica-Like Clays (Illite, Celadonite and Glauconite).- 3.2.2 Smectites.- 3.2.3 Kaolinite Minerals.- 3.2.4 Chlorites and Related Minerals.- 3.2.5 General Chemical Identity of the Clays.- 3.3 Physical Properties of Clay Minerals.- 3.3.1 Clay-Water Mixtures.- 3.3.2 Clay Shapes.- 3.4 Thermal Stability of Clays and Clay-Water Mixtures.- 3.5 Kinetics.- 3.5.1 Grain Size.- 3.5.2 Heating Rate.- 3.6 Summary.- 4 Origin of Clay Resources.- 4.1 Segregation of the Elements by Weathering.- 4.2 Weathering of Minerals.- 4.3 From Rocks to Soils to Sediments.- 4.3.1 Weathering Profiles.- 4.3.2 Transportation by Water Flow, Grain-Size Sorting.- 4.3.3 Transport and Deposition of Clays.- 4.3.4 Wind Transport.- 4.3.5 Burial of Sediments.- 4.4 Hydrothermal Alteration.- 4.5 Sources of Materials Suitable for Ceramics.- 4.5.1 Clays.- 4.5.2 Non-Clay Grains.- 5 Physical and Chemical Processes of Making Ceramics.- 5.1 Plasticity.- 5.2 Mineral Temper Grains.- 5.2.1 Natural Mineral Grains.- 5.2.2 Decantation and Separation of Natural Mineral Temper Grains.- 5.2.3 Tempering by Mixtures of Source Materials.- 5.2.3.1 Mixtures of Clays and Non-Clay Grains from Different Sources.- 5.2.3.2 Mixtures of Clay Sources.- 5.3 Decorations and Surfaces.- 5.3.1 Surface Smoothing.- 5.3.2 Slip.- 5.3.3 Paint.- 5.3.4 Glazes.- 5.4 Firing and Furnaces.- 5.4.1 Variables of Transformation to Make a Ceramic.- 5.4.1.1 The Firing Process: Time and Temperature.- 5.4.1.2 Stages of Transformation in Time-Temperature Coordinates.- 5.4.1.3 Paste Composition and Fusing Agents.- 5.4.1.4 Reduction of Iron.- 5.4.1.5 Particle Size.- 5.4.2 Firing Practices.- 5.4.2.1 Firing on the Ground.- 5.4.2.2 Pit Firing.- 5.4.2.3 Kilns.- 5.4.3 Summary of Factors in the Formation of a Ceramic Body During Firing.- 5.5 Structure, Porosity and Density of Ceramics: Non-Plastics, Clays and Pores.- 5.5.1 Pores.- 5.5.1.1 Primary Pores.- 5.5.1.2 Secondary Pores.- 5.5.1.3 Microporosity.- 5.5.2 Temper, Material and Firing.- 5.5.3 Thermal Properties of Oriented Clays.- 5.5.4 Hardness.- 5.6 Oxidation-Reduction Effects.- 5.7 Oxidation-Reduction Cycles.- 5.8 Mineral Reactions During Firing.- 5.9 Families of Ceramic Products.- 5.9.1 Earthenware.- 5.9.2 Pottery, Terra Cotta and Faience.- 5.9.3 Stoneware.- 5.9.4 Porcelain.- 5.10 Summary.- 6 The Making of Pots.- 6.1 Temper and Tempering.- 6.2 Raw Materials.- 6.2.1 Clay Material.- 6.2.2 Tempering Materials and Methods of Tempering.- 6.2.3 Tempering and Temper Identification.- 6.3 Making a Pot: Physical and Chemical Reactions.- 6.3.1 Needs as a Function of the Object.- 6.3.1.1 Plasticity and the Role of Temper and Non-Plastics.- 6.3.1.2 Drying and Shrinkage.- 6.3.1.3 Material Expansion.- 6.3.1.4 Grain Angularity.- 6.3.2 Paste as Related to Function, Form and Manufacturing Requirements.- 6.3.3 Needs as a Function of Use of the Object.- 6.3.3.1 Durability and Breakage Resistance; Strength and Hardness.- 6.3.3.2 Porosity, Density, Permeability, Impermeability.- 6.3.3.3 Thermal Stress Resistance and Thermal Conductivity.- 6.4 Preparation of Material.- 6.5 Forming Techniques.- 6.6 Surface Coatings as Related to the Function of the Ware.- 6.7 Firing and Furnaces.- 6.7.1 Open Fires.- 6.7.2 Pit-Kilns, Semiclosed Structures, Open Kilns.- 6.7.3 Kilns.- 6.7.4. Needs of a Type of Paste Related to the Type of Firing.- 6.8 Summary.- 7 Optical Observation of Ceramics.- 7.1 Introduction.- 7.2 Methods: How Can One See a Ceramic Sherd?.- 7.2.1 Computer Scanner.- 7.2.2 Binocular Microscope.- 7.2.3 Petrographie Microscope.- 7.3 Types of Characteristics Observed: What Can One See in a Ceramic Sherd?.- 7.3.1 Slip, Glaze or Paints.- 7.3.2 Temper Grains and Clays.- 7.3.3 Temper Grains and Size Distribution.- 7.3.4 Grain Shapes.- 7.3.4.1 Crystal Shapes.- 7.3.4.2 Angularity.- 7.3.4.3 Size Distribution of Temper Grains.- 7.4 Identification of Different Techniques in Paste Preparation.- 7.5 Texture of Paste.- 7.6 Summary.- 8 Ceramics and Archaeology: Case Studies.- 8.1 Yellow Garnets and Trafficking Wine.- 8.2 Iron Age Pottery in Southwestern England and its Geological Sources.- 8.3 Whole-Sample Compositions of Some Sigillate ware Produced in France.- 8.3.1 Lezoux Samples.- 8.3.2 Identifying Production Areas.- 8.3.3 Lezoux Coarse or Common Ware.- 8.3.4 Specific Problems of Archaeological Interest Using Sigillate Ware Data.- 8.3.4.1 Arezzo Moulds.- 8.3.4.2 Atevis Workshop.- 8.4 Prehistoric Peru.- 8.4.1 Petrographie Analysis.- 8.4.2 Modal Analysis.- 8.4.3 Chemical Analysis.- 8.5 Modern Ceramic Production in the Andes.- 8.5.1 Production Setting.- 8.5.2 Petrographic Analysis.- 8.5.2.1 The Unprepared Black Clay.- 8.5.2.2 The Unprepared Yellow Temper.- 8.5.2.3 The Clay-Temper Mix.- 8.5.3 The Fired Pot Fragment.- 8.5.4 Image Analysis.- 8.6 Clay Characterization by SEM (Scaning Electron Microscope).- 8.7 Determination of Firing Temperature.- 8.8 Mössbauer Spectroscopy.- 9 Some Current Analysis Methods.- 9.1 Ceramic Analysis.- 9.1.1 What For and How?.- 9.1.1.1 Classification.- 9.1.1.2 The Study of Pottery Technology.- 9.1.1.3 Provenance Studies.- 9.1.2 Quantitative Studies.- 9.1.3 Use of Qualitative and Quantitative Studies.- 9.1.4 Sample Size and Qualitative and Quantitative Studies Versus Time and Cost Invested.- 9.2 Physical and Chemical Analysis Methods.- 9.3 A Brief Description of the Methods.- 9.3.1 Visual Methods.- 9.3.1.1 Binocular Microscope.- 9.3.1.2 Petrographic Microscope.- 9.3.1.3 Computer Scanner and Video Systems.- 9.3.1.4 Electron Microscopes.- 9.3.1.4.1 Scanning Electron Microscope (SEM).- 9.3.1.4.2 Transmission Electron Microscopes (TEM).- 9.3.1.4.3 High-Resolution Transmission Electron Microscopes (HRTEM).- 9.3.2 Mineral Identification by Non-Optical Metho…