Raw Materials for Archaeological Pottery from the Campania Region of Italy: A Petrophysical Characterization

We performed petrophysical analyses on 34 clayey samples of different geological origin within the Campania region of Italy in order to determine possible sources of raw materials used to produce ancient pottery. Possible raw material sources can be grouped into high‐CaO clays (HCC) and low‐CaO clays (LCC). HCC are mainly represented by more recent (Miocene‐Pleistocene) basinal sediments whereas LCC tend to be associated with basinal, alluvial, and pyroclastic deposits. A chemical comparison between clayey raw materials, modern ceramic replicas, and Campanian archaeological ceramics of several typologies (common ware, cooking ware, fine tableware, amphorae, and bricks) from 8th century B.C. to the Middle Ages (a total of 350 ceramic samples) indicates that HCC were extensively used for common wares and that these were either mixed with temper or levigated. In contrast, most of the LCC were used for the production of cookware. We also analyzed the technological potential of the sampled raw materials, taking into consideration their actual and possible uses. We observed that most HCC deposits were well suited for tableware and amphorae, whereas LCC were better for cookware and some fine tableware.     

The source of raw materials for Roman pottery from Leptiminus,Tunisia

Leptiminus, a Roman port city on the west coast of Tunisia, North Africa, exported olive oil and a garum fish paste to Rome. Excavations have uncovered many facilities including kilns and a potter's workshop, indicating an extensive ceramic industry. The vessels, manufactured at Leptiminus, included African red‐slip fineware, coarseware, and amphorae. A petrographic study of pottery sherds showed them to contain very similar temper, rounded aeolian sand grains and limestone, but varying in proportions to produce different textures. An investigation of the source of raw materials for the pottery found three distinct types of clay within a 50 km radius of Leptiminus: grey Miocene, brown Pliocene, and green Late Pliocene clay. Statistical analysis of trace element compositions, using induced neutron activation, of clays and sherds showed that the Pliocene brown clay was used to create all types of pottery. The specific clay horizon, used in Roman times, has apparently been removed by quarrying. However, a lateral continuation of this bed was found 7 m beneath the Leptiminus site 290. © 2002 Wiley Periodicals, Inc.     

Lead isotopic analysis within a multiproxy approach to trace pottery sources. The example of White Slip II sherds from Late Bronze Age sites in Cyprus and Syria

Lead isotope analyses were carried out on fragments of White Slip II ware, a Late Bronze Age Cypriote pottery ware, and on raw materials possibly used for their production. Sherds originate from three Late Bronze Age sites (Hala Sultan Tekke and Sanidha in Cyprus and Minet el-Beida in Syria) and clays come from the surroundings of Sanidha, a production site for White Slip ware. X-ray fluorescence (XRF) and a Principal Component Analysis (PCA) are combined with Pb isotope analyses to further investigate the effectiveness of the latter method within a multiproxy approach for pottery provenance study. The pottery sherds from the three sites are compared between themselves and with potential raw material. Additional X-ray diffraction (XRD) and analyses using a scanning electron microscope (SEM) equipped with an energy dispersive X-ray detection (EDX) facility were performed on selected sherds and clays. This work confirms that the clay source used for pottery production in Sanidha derives from local weathered gabbro. It also shows that different origins can be proposed for White Slip II ware sherds from Hala Sultan Tekke and Minet el-Beida and that clays were prepared prior to White Slip II ware production. It finally confirms the effectiveness of Pb isotopes in tracing pottery provenance not only by comparing sherd assemblages but also by comparing sherds to potential raw materials.     

An exploration of potential raw materials for prehistoric pottery production in the Tao River Valley,Gansu Province,China

Northwest China is known for its Majiayao-style Neolithic painted pottery which has received much praise for its high level of craftsmanship, yet its chain of production, in particular the step of raw material selection, is still poorly understood. To fill this lacuna, the present study explores the raw materials used in producing these wares from a geological and technological perspective. At its core stands the first geoarchaeological survey conducted around the eponymous site of Majiayao which collected 47 samples of raw materials suitable for ceramic production including clay, loess and rocks, which were all analysed macroscopically. A selection was analysed using thin-section petrography, and a subset of the clay and loess samples were subjected to firing experiments. Additionally, three clay samples were analysed by scanning electron microscope with energy-dispersive X-ray spectrometer to understand their composition and behaviour in ceramic production. These were then compared to archaeological ceramics, thus providing insights into raw-material availability and selection that will be of importance not only for research on Majiayao-style pottery but also for later-period ceramics produced in the area. This research shows how an archaeologically informed geological survey can contribute insights into human–environment interaction in early pottery production, especially the interplay between raw-material availability, technological know-how and potters' choices.     

Using Lead Isotopes to Determine Pottery Provenance in Cyprus: Clay Source Signatures and Comparison with Late Bronze Age Cypriote Pottery

This paper presents the lead isotopic composition of potential clay sources for pottery production, collected in the four major geological zones of Cyprus (Troodos Ophiolite, Circum Troodos Sedimentary Succession, Mamonia Terrane, Kyrenia Terrane) and evaluates its usefulness in Cypriote pottery provenance studies. The clay isotopic signatures from the four zones are compared to each other and to the isotopic composition of various utilitarian pottery wares from three Late Bronze Age sites, respectively located in southern Cyprus (Alassa‐Pano Mandilaris), east Cyprus (Enkomi), and southeast Cyprus (Hala Sultan Tekke). It also explores the potential of this method to better discriminate between potential raw materials used for the production of Base‐ring ware, one of the most characteristic fine pottery of Late Bronze Age Cyprus, which was widely spread in the Eastern Mediterranean (Courtois, 1981; Vaughan, 1991, 1994). Results show that three main lead isotopic fields can be distinguished among the Cypriote clay sources and the comparison of Plain sherds with the clay sources allows discrimination between local products and imports. They also clearly indicate that all the Base‐ring sherds analyzed in this study were made of the clays from the Kathikas Formation that crops out in only limited parts of southwest Cyprus.     

Geoarchaeological investigations of the “potters' quarter” at Sagalassos,southwest Turkey

The potters' quarter of the ancient city of Sagalassos, southwest Turkey, was one of the largest and most enduring ceramic‐producing manufactories in the eastern Mediterranean. The objective of our study was to determine environmental circumstances that favored development of different clay resources in the territory of Sagalassos and to assess utilization of these resources in the local pottery manufactory. The potters' quarter was established where, owing to favorable geological circumstances, a large clay body had developed. The bedrock in the potters' quarter, a tectonized ophiolite sequence, has synclinal structure; hence, surface runoff and groundwater tend to accumulate in its center. The weathering of the basic rock formed a smectite‐rich clay with vertic properties. This clay was mined in antiquity, and mineralogical and chemical analyses indicate that it was used for the production of local ceramics from Hellenistic to Byzantine times. It is likely that colluvium on top of the ophiolitic clay at the potters' quarter is related to deforestation and slope processes after the potters' quarter was abandoned. In sum, environmental circumstances determined the location of the artisanal quarter of Sagalassos, with its clay quarrying operation and ceramic manufactory. However, for the local mass‐produced Sagalassos red slip ware, the results of our chemical and mineralogical analyses indicate that a different, more suitable clay was used: detrital lake sediments, rich in chlorite and chlorite/smectite mixed layers, located about 8 km from the original artisanal quarter. The choice for this clay was determined both by the presence of a suitable clay deposit, as well as socio‐economic circumstances such as land ownership. The site of Sagalassos yielded unique evidence of mining of clay at a ceramic production site, as well as import of nearby clays. The local and imported clays were used side‐by‐side, but one for the production of common wares and building ceramics, and the other for the manufacturing of luxury fine tablewares. © 2003 Wiley Periodicals, Inc.     

A geological study of clayey laterite and clayey hydromorphic material of the region of Yaoundé (Cameroon): a prerequisite for local material promotion

A geological survey carried out in the Yaoundé (Cameroon) region has revealed the presence of homogeneous clayey laterite in the upper part of a laterite cover on interfluves, thickest on hills (780–800 m altitude) where ferricrete is absent, and clayey heterogeneous hydromorphic material in valleys. We present in this paper the physical, mineralogical and geochemical properties of these occurrences and discuss their potential as raw material for pottery, manufacture of bricks and tiles. These clayey raw materials are mostly made up of fine particles (ranging from 55 to 60% clay + silt in the clayey laterite, more than 70% clay + silt in the clayey hydromorphic material). Their chemical composition is characterized by silica (<60% SiO₂), alumina (<35% Al₂O₃) and iron (ranging from 3 to 14% Fe₂O₃). Their main clay minerals are disorganized and poorly crystallized kaolinites. The average limits of liquidity (44.56% versus 91.58%) and limits of plasticity (22.4 versus 45.93) revealed that clayey hydromorphic material has the greatest plasticity. The studied raw materials are suitable for making pottery as well as the manufacture of bricks and tiles. However, the high iron content in the clayey laterite (between 11 and 12% Fe₂O₃) prevents their efficient use in the manufacture of ceramics.     

Composition,Technology of Manufacture,and Circulation of Hellenistic Pottery from the Eastern Adriatic: A Case Study of Three Archaeological Sites along the Dalmatian Coast,Croatia

Archaeological excavations in Dalmatia have yielded a large amount of Hellenistic pottery that has yet to be archaeometrically analyzed. Stylistic analyses suggest that some vessels were imported, but the bulk of the material must have been produced locally. Our objectives are to demonstrate local ceramic production in both Greek colonies and native settlements in Dalmatia, and also to report on the composition and manufacture technology associated with this pottery. We examine 36 Hellenistic potsherds recovered from the coast of Croatia: a sanctuary on Cape Ploča, the native settlement of Resnik, and the Greek colony Issa. For the first time, archaeometric evidence supporting local production in Resnik is presented, while two local manufacturing centers are proposed for the bulk of the Cape Ploča pottery. The term Dalmatian production is suggested here to describe these indigenous ceramics. Material characteristics of the Issa samples suggest local colonial production and sophisticated ceramic technology.     

Petrographic and geochemical characterization of Archaic‐Hellenistic tableware production at Solunto,Sicily

A selected assortment of Archaic‐Hellenistic tableware samples from Solunto, a Phoenician‐Punic site located 20 km east of Palermo (Sicily), has been subjected to thin‐section petrography and chemical analysis (XRF). In this settlement several ceramic kilns remained operative over a long time period (7th to 3rd century B.C.). The main goal of this analytical study is to distinguish the ceramics manufactured locally from regional and off‐island imports. Analytical results were matched to similar data concerning local natural clay sources and to coeval tableware productions from other sites in the same area. The ceramic pastes used by the ancient craftsmen of Solunto in the case of this class of pottery could be differentiated clearly by their petrochemical characteristics. We conclude that ceramics were locally produced far beyond satisfying just internal consumption needs, indicating interaction of Solunto with neighboring Greek colonies, indigenous people, and Phoenician‐Punic colonies of Sicily. © 2009 Wiley Periodicals, Inc.     

Pliocene clays from Aegina (Greece): Reference material for chemical provenance studies on bronze age pottery from the Island

Normally, the use of clays as reference materials in chemical provenance studies of ancient ceramics is complicated due to the original clay paste processing. The primary mixing and/or refining of raw materials during pottery production makes a straightforward comparison of archaeological ceramics with extant geological materials difficult if not impossible in many cases. However, in the case of Pliocene clays from Aegina (Greece), which were examined chemically and mineralogically and compared with Bronze Age pottery produced on the island, a successful exception can be presented. The chemical composition of a large group of Aeginetan pottery resembles the chemical composition of clays from a deposit in close vicinity to the main Bronze Age settlement of the island. Clays from specific outcrops exhibit considerable chemical and mineralogical homogeneity, and the suitability of those clays for pottery production apparently made substantial clay paste processing unnecessary. © 2004 Wiley Periodicals, Inc.     

Nickel,molybdenum, and cobalt in the black shales of the Bazhenov Formation of the West Siberian basin

It was shown that the contents of Ni, Mo, and Co in the siliceous clay black shale rocks of the normal sections of the Bazhenov Formation are several times higher than the global mean contents of these elements in black shales. These rocks have the highest contents of pyrite and organic carbon and show evidence for strongly reducing formation conditions at the slowest background rate of sedimentation of their material. A transition from the siliceous clay rocks to the mudstones of normal section, which are considered as turbidites, and further to the mudstones and clayey silt rocks of the so-called anomalous sections (deposits of submarine deltas and canyons) is accompanied by sequential depletion in pyrite and organic carbon, a decrease in indicators of the reduction level of the sedimentation environment, and an increase in sedimentation rate and clay material content. Simultaneously, the contents of the elements of interest decreases in the sequence Mo > Ni > Co. In the rocks of anomalous sections, the contents of these elements decrease to the level of their mean abundances in clays.     

It all comes out in the wash: Actualistic petrofacies modeling of temper provenance,Tonto Basin,Arizona, USA

Prehistoric potters frequently tempered their pottery with sand, the provenance of which can be established petrographically. In the Tonto Basin of central Arizona, the bedrock geology is highly variable, giving rise to geographically unique sands. Zones of sands with similar compositions can be modeled at an archaeologically relevant scale. Here we use the actualistic petrofacies concept, the Gazzi–Dickinson point‐counting technique, and multivariate statistics to create a petrofacies model, then apply it to sand‐tempered utilitarian pottery recovered from three Tonto Basin project areas. Data analysis reveals strong temporal and spatial ceramic production and consumption patterns. Production of pottery for exchange was established in at least one petrofacies ca. A.D. 600–950, with increasing specialization through time. By ca. A.D. 1150, corrugated wares had been added, and specialized production by ware was established in two petrofacies. Provenance evidence suggests different regional affiliations for groups in different parts of the basin. © 2001 John Wiley & Sons, Inc.     

宿迁市晓店陶瓷矿床特点及评价

晓店陶瓷矿床位于郯庐断裂带内，并分为瓷石，陶土和陶瓷土三大类型，其中瓷石矿产于下白垩统青山组火山岩中，陶土矿产于上白垩统王氏组中，瓷土矿产于上新统宿迁组中。测试结果表明，该陶瓷矿是较理想的建筑陶瓷原料，并可望成为江苏新的陶瓷原料基地。     

Provenance and microprobe assays of phyllite‐tempered ceramics from the uplands of central Arizona

The ceramics in use across a broad upland zone of central Arizona during the early Classic period (ca. A.D. 1100–1300) were characterized by a lack of mineralogical variability; nearly all of the clay containers were tempered with one rock type, phyllite. Consequently, nearly all of the upland pottery is assigned to a single pottery type, Wingfield Plain. This compositional uniformity has frustrated ceramic provenance studies, and, as a result, little has been learned previously about the organization of ceramic production and exchange in the upland territory. There are, however, considerable and interpretable chemical differences in the phyllite‐tempered wares, as shown with microanalyses of the temper fragments and pottery clay fractions with an electron microprobe. The chemical patterning is useful for investigating issues pertaining to the upland zone, including the organization of ceramic manufacture, community arrangements, and pottery transactions during a time of prevalent hostilities in central Arizona. © 2008 Wiley Periodicals, Inc.     

Raw Materials and Pottery Production at the Late Bronze and Iron Age Site of Puig de Sa Morisca,Mallorca, Spain

This paper presents an analytical study of LateBronze andIronAge ceramics and natural clay deposits from the archaeological site ofPuig deSa Morisca in southwestMallorca,Spain. In our study, we combine petrographic, micropaleontological, mineralogical (X‐ray powder diffraction) and textural (laser particle size) analyses of sherds and local clays that may have been used as raw material in ceramic production. This approach allowed us to compare the ceramics’ formal characteristics with those observed in nearby plastic clays and assess raw clay procurement and paste preparation. The results indicate the use of local (<500 m distance) calcareous clays throughout theLateBronze andIron ages. This raw material was mixed with other coarser clays or crushed calcite, as well as other calcareous tempers, such as breccias or calcarenites, located close to the site. The results demonstrate that the same clay deposit was used to make ceramic vessels following different technological choices and recipes. Thus, local communities established a strong connection with the same raw materials through time that were located within the potters’ preferential range of exploitation.     

Submergence and uplift of settlements in the area of Helike,Greece, from the Early Bronze Age to late antiquity

Excavations in the Helike Delta on the Gulf of Corinth have brought to light architectural remains from the Early Bronze Age (EBA), Geometric, Classical, Hellenistic, Roman, and Byzantine periods. Borehole results suggest that a lagoon intermittently occupied much of the delta during the Holocene. We discovered a well‐preserved EBA settlement about 1km inland from the present shore, buried under 3 to 5m of fine sediments containing marine, brackish, and freshwater microfossils. A Classical site 130m away, buried under 3m of similar sediments, may have been destroyed by the earthquake and tsunami of 373 B.C., which submerged the city of Helike. Possible tsunami evidence is noted. Although the EBA and Classical sites were both long submerged and buried by lagoonal sediments, tectonic uplift has raised both horizons above sea level. A shallow black clay layer suggests that a marsh covered the Classical and EBA sites in Byzantine times. © 2011 Wiley Periodicals, Inc.     

Engineering properties of unfired clay masonry bricks

The shortage of low cost and affordable housing in the UK has led to many investigations into new building masonry materials. Fired clay masonry bricks are conventionally used for mainstream masonry wall construction but suffer from the rising price of energy plus other related environmental problems such as high energy usage and carbon dioxide emission. The use of stabilised unfired clay bricks for masonry construction may solve these problems.This paper reports on the engineering properties of unfired clay bricks produced during the first industrial trial of unfired clay material development carried out at Hanson Brick Company, in Stewartby, Bedfordshire, under the Knowledge Exploitation Fund (KEF) Collaborative Industrial Research Project (CIRP) programme. The mixes were formulated using a locally available industrial by-product (Ground Granulated Blastfurnace Slag — GGBS) which is activated with an alkaline (lime or Portland cement) combined with clay soil. Portland cement was not used in the formulation of the unfired stabilised masonry bricks, except as a control, which is a significant scientific breakthrough for the building industry. Another breakthrough is the fact that only about 1.5% lime was used for GGBS activation. This level of lime is not sufficient for most road construction applications where less strength values are needed and where 3–8% lime is required for effective soil stabilisation. Hence, the final pricing of the unfired clay bricks is expected to be relatively low.The laboratory results demonstrate that the compressive strength, moisture content, rate of water absorption, percentage of void, density and durability assessment (repeated 24-hour freezing/thawing cycles) were all within the acceptable engineering standards for clay masonry units. The paper also discusses on the environmental performance of the unfired clay in comparison to the bricks, used in mainstream construction of today. The bricks produced using this technology can be used for low-medium cost housing and energy efficient masonry wall construction.     

A plains ceramic clay source characterization by comparative geochemical and petrographic analyses: Results from the Calhan Paint Mines,Colorado, U.S.A.

The Calhan Paint Mines District, 5EP3258, Colorado, presents exposures of an exceptional clay source. When the area also produced prehistoric Ceramic stage sites, it provided the opportunity for both pottery and potential clay source analysis by optical petrography, X‐ray diffraction, and neutron activation. Although the main purpose of this study is the characterization of the ceramics and outcrop clays, results from a limited number of samples suggest that the colorful clays, the figurative “paints,” of the Calhan Paint Mines were purposely used in prehistoric times as clay source materials for ceramic production. The Calhan Paint Mines are quite possibly the only prehistoric Plains Ceramic stage clay source currently confirmed within the state of Colorado. © 2002 Wiley Periodicals, Inc.     

Compressive strength and microstructural analysis of unfired clay masonry bricks

This paper reports on the compressive strength and microstructure of unfired clay masonry bricks. Blended binders comprising of lime-activated Ground Granulated Blastfurnace Slag (GGBS) and Portland Cement (PC)-activated GGBS were used to stabilise Lower Oxford Clay (LOC) for unfired masonry brick production. The compressive strength of the stabilised bricks incorporating lime–GGBS–LOC was higher than that of PC–GGBS–LOC. Scanning Electron Microscopy (SEM) with a Solid-state Backscattered Detector (SBD) and Energy Dispersive X-ray (EDX) analysis was employed to obtain a view of the microstructure and to conduct an analysis on the morphology and composition of the dried unfired clay brick samples, after 28 days of moist curing. The analytical results together with the physical observations have shown the formation of Calcium Silicate Hydrate (C-S-H) gel and additional pozzolanic (C-S-H) gel. The quantification of the compound content of the unfired bricks showed the presence of Calcite (CaCO₃), Quartz (SiO₂), Alumina (Al₂O₃) and Wollastonite (CaSiO₈) crystals. Traces of other crystals were also detected.     

Flow dynamics at the origin of thin clayey sand lacustrine turbidites: Examples from Lake Hazar,Turkey

Turbidity currents and their deposits can be investigated using several methods, i.e. direct monitoring, physical and numerical modelling, sediment cores and outcrops. The present study focused on thin clayey sand turbidites found in Lake Hazar (Turkey) occurring in eleven clusters of closely spaced thin beds. Depositional processes and sources for three of those eleven clusters are studied at three coring sites. Bathymetrical data and seismic reflection profiles are used to understand the specific geomorphology of each site. X‐ray, thin sections and CT scan imagery combined with grain‐size, geochemical and mineralogical measurements on the cores allow characterization of the turbidites. Turbidites included in each cluster were produced by remobilization of surficial slope sediment, a process identified in very few studies worldwide. Three types of turbidites are distinguished and compared with deposits obtained in flume studies published in the literature. Type 1 is made of an ungraded clayey silt layer issued from a cohesive flow. Type 2 is composed of a partially graded clayey sand layer overlain by a mud cap, attributed to a transitional flow. Type 3 corresponds to a graded clayey sand layer overlain by a mud cap issued from a turbulence‐dominated flow. While the published experimental studies show that turbulence is damped by cohesion for low clay content, type 3 deposits of this study show evidence for a turbulence‐dominated mechanism despite their high clay content. This divergence may in part relate to input variables, such as water chemistry and clay mineralogy, that are not routinely considered in experimental studies. Furthermore, the large sedimentological variety observed in the turbidites from one coring site to another is related to the evolution of a sediment flow within a field‐scale basin made of a complex physiography that cannot be tackled by flume experiments.