Research design in digital luminance analysis

The prevalence of digital image analysis in studies spanning a wide range of fields makes the importance of set-up design decidedly important for repeatability and testing between studies, especially for those interested in the analysis of microscopic properties. This note outlines some important guidelines for setting up an image analysis protocol, and provides a case study based on the digital analysis of dental cement. Our method allowed for us (1) to get data through the conversion of optical luminance into numerical values and (2) to accurately measure image features through numerical analysis.     

Laboratory and in situ assays of digital image analysis based protocols for biodeteriorated rock and mural paintings recording

Rock art paintings, and in general mural paintings, are one of the many elements of cultural heritage complex systems. As the different elements of a system have diverse spatial positions, spatial recording allows understanding their interactions. Thus, a useful approach to mural paintings recording is to understand it as a microcartography issue, managing each element of the system as a cartographic coverage.     

Long-term clay raw material selection and use in the region of Classical/Hellenistic to Early Byzantine Sagalassos (SW Turkey)

A provenance study was carried out on coarse ceramics from the Classical/Hellenistic to Mid-Byzantine city of Sagalassos, SW Turkey. The ceramics were sampled from the excavations of the city, and clay raw materials were sampled throughout its ancient territory. Used techniques were optical microscopy and electron microprobe analysis on thin sections, geochemical analysis (fusion ICP/MS and mineralogical analysis (X-ray diffraction). The geochemical/mineralogical diversity in the ceramics is not as wide as for the clay raw materials. It seems that even at the restricted scale of this study, the resources were limited to the area around the ancient site. The differences between the ceramics are likely due to the use of different ophiolitic clay bodies being exploited for their production.     

Using hearths for temper: petrographic analysis of Middle Woodland charcoal-tempered pottery in Northeast Florida

Charcoal-tempered pottery is uncommon in North America, but was produced with notable frequency in Northeast Florida from ca. AD 300–600. Thirty-six thin sections of pottery were analyzed by petrographic analysis and compared to 10 clay samples in order to characterize the paste of charcoal-tempered wares in terms of charcoal and mineralogical composition and abundance, assess the number of clay sources used to make the pottery, identify the species of wood represented in charcoal inclusions, and infer techniques of ceramic production. This analysis identified four temper categories, three texture groups, and three distinct clay resources used to make charcoal-tempered pottery, all of which were likely local to Northeast Florida. Identified wood taxa include pine (Pinus sp.), cedar (cf. Juniperus sp.), cypress (cf. Taxodium sp.), and sassafras (Sassafras albidum), with pine suspected to be the most common. These genera of charred wood, which exhibit minimal shrinkage in the samples, along with the prevalence of bone and grog inclusions, indicate that hearth contents were processed as temper, sometimes in combination with quartz sand. Potential reasons for the use of hearth contents as temper are considered.     

Temper mixture models and assessing ceramic complexity in the emerging Tarascan state

This study presents compositional data from ceramics drawn from surface survey and controlled excavations from three prehispanic sites within the relatively small Lake Pátzcuaro Basin, representing a ceramic sequence stretching nearly 1500 years, from the Preclassic to Late Postclassic Tarascan state (ca. 50 B.C.–1525 A.D.). Using neutron activation analysis, we identify compositional groups and model the importance of volcanic materials as temper in the construction of prehispanic ceramics by matching mathematical simulations of clay–ash mixes to the compositional groups. Rather than discreet clay resources and spatially circumscribed production, we argue for a broadly dispersed and highly varied organization of pre-Tarascan and Tarascan state ceramic production in which the potters' distribution and use of specific volcanic ashy additives, not clays, structured the organization of production.     

Re-examining the Egyptian colonial encounter in Nubia through a compositional,mineralogical, and textural comparison of ceramics

Textural, mineralogical, and X-Ray fluorescence (XRF) analyses are used as a cost effective method to distinguish for the first time ancient Egyptian and Nubian-style ceramics found in Nubia. Textural and mineralogical data suggest that Nubian-style sherds are mixtures of sand, silt, and clay sediment that is generally finer grained and poorer in quartz than is the sediment mixture used to produce Egyptian-style pottery. Chemical data also establish a significant difference in the amount of chemical variation found within each style population, but nonetheless supports a considerable overlap in the possible provenance of both styles. Observations and data obtained during this study indicate that standardized, Egyptian-style manufacturing was introduced into Nubia under colonialism, without substantially altering the diversity of native methods of production.     

Hohokam and Patayan interaction in southwestern Arizona: evidence from ceramic compositional analyses

Ceramic raw material use is one line of evidence for prehistoric territorial boundaries and social interaction. In this paper, we characterize the raw materials used by Hohokam and Patayan potters along the western Hohokam frontier, using data from oxidation analysis, laser-ablation inductively-coupled plasma spectrometry, and petrographic analysis. The sample includes 150 sherds from three sites (AZ Z:1:29[ASM], AZ Z:1:30[ASM], and BMGR-02-F-04) south of Gila Bend, Arizona. Similar Lower Gila River sediments were used for Hohokam and Patayan ceramics during the period A.D. 700–1150. Patayan potters apparently used clay sources from an area dominated by Hohokam settlements, and their ceramics were transported at least 50 km into the desert interior, perhaps representing seasonal movements between the river and the desert.     

Determining the provenance of black limestone artifacts using petrography,isotopes and EPR techniques: the case of the monument of Bocco

This paper investigates the provenance of the black limestone of the monument known as Bocco, named after the king of Mauretania who presented Silla with this work as a sign of his submission to the power of Rome. A multi-method approach, comprising petrographic observations, carbon and oxygen isotope composition and electron paramagnetic resonance (EPR) spectra characteristics, was used for this purpose. The monument is part of a reconstruction of a rectangular base (approx. 8 × 2 m) which is likely to have served as the base for a bronze statuary group and is currently composed of six blocks of limestone whose exterior is engraved with a fine frieze. The results of the different analyses were compared with the data of a published database of the most important black limestone quarries exploited during Roman times in the Mediterranean area. The petrographic and physico-chemical parameters did not prove to be very effective in determining the provenance of the black limestone of Bocco; the isotopes result even raised some uncertainty as to whether all six blocks came from the same quarry, though this doubt was dispelled by the EPR data and, above all, by the evident petrographic similarity between them. Differences in the isotopic composition of the various blocks may be due to an in situ rock alteration process caused by interaction with an aqueous fluid. It was, however, impossible to determine with certainty the origin of the material of the stone artifact using the database available; it is possible that the black limestone of Bocco came from an ancient quarry that is likely to be located in north western Africa but has not yet been uncovered. An alternative hypothesis, according to which the limestone used for the monument of Bocco came from the ancient quarry of Ain el Ksir, one of the Tunisian quarries present in the database, is also discussed.     

In the beginning: Marhashi and the origins of Magan's ceramic industry in the third millennium BC

Ceramics from the Jiroft plain in southeastern Iran are compared with material of Umm an-Nar-type dating to the mid- and late third millennium BC in the Oman Peninsula. Technological and stylistic comparisons suggest the strong possibility that potters from the Iranian side of the Straits of Hormuz may have been the instigators of Magan's earliest ceramic industry.     

Ceramic production,consumption and exchange in the Banda area,Ghana: Insights from compositional analyses

Ceramic production, exchange and consumption in the Banda area, west central Ghana has been affected by historical developments ranging from recent competition with alternative vessels (made of metal and plastic) to political economic upheavals that altered community relationships within and outside the region. In this study, we explore spatial and temporal patterning in pottery production, exchange and consumption using a combination of analytical techniques. Instrumental neutron activation analysis (INAA) of a large sample (491 specimens) of archaeological and ethnographic pottery, clay and temper samples from sites across the Banda area has led to the identification of seven compositional groups whose differential distribution implies shifts in resource selection through the last thousand years. Laser ablation-ICP-MS analysis was used to explore the effects of distinctive tempering agents (crushed slag) on the bulk chemical signature of a subset of Banda ceramics, while petrographic analysis provides insight into the preparation of ceramic fabrics. We integrate insights from these diverse physical studies to investigate the dynamics of pottery production, exchange and consumption over the course of the last millennium in the Banda area and explore potential linkages with broader political economic transformations.     

Understanding ceramic variability: an archaeometrical interpretation of the Classical and Hellenistic ceramics at Düzen Tepe and Sagalassos (Southwest Turkey)

Within the aim of contributing to the artisanal craft history at Sagalassos (SW-Turkey), an archaeometric programme including thin section analysis, ICP-MS and multivariate statistics was developed to define the variability on a provenance and/or technological scale of the Classical/Hellenistic ceramic assemblage of Sagalassos and Düzen Tepe. The obtained data were used to evaluate the extent and variation of local pottery production. Petrographic and geochemical analysis as a grouping technique proves to be conditional for documenting the variation in ceramic wares present on both archaeological sites. Elemental evidence supports local production activities between Classical and Hellenistic times, documenting a deliberate change in treatment of raw materials during the Late Hellenistic period in function of ware groups.     

Geochemical and mineralogical analysis of stone anchors from west coast of India: provenance study using thin sections,XRF and SEM-EDS

Stone anchors have been recovered along the Indian coast as a part of the maritime archaeological studies at the National Institute of Oceanography (NIO), Goa. Study of stone anchors provides clues to understand the ancient maritime trade contacts of India with other countries. These anchors resemble those found in the Mediterranean Sea, Persian Gulf and Red Sea Coast. Underwater explorations at Bet Dwarka, Dwarka, Goa, Visawada and Somnath have yielded stone anchors of widely varying shapes, sizes and weights ranging between 16 and 410 kg. Sixteen (10 Indo-Arabian, 4 Ringstone and 2 Single hole type) of the total of 269 stone anchors have been studied to determine provenance of rock through petrographic analysis using thin section studies, X-ray Fluorescence (XRF), and Scanning Electron Microscope – Energy Dispersive Spectrometer (SEM-EDS).     

Multitemporal analysis for preservation of obsidian sources from Melka Kunture (Ethiopia): integration of fieldwork activities,digital aerial photogrammetry and multispectral stereo-IKONOS II analysis

An integrated analysis of recent satellite imageries and dated aerial photos demonstrated to be a good investigation tool (Gallo et al., 2009) for the identification of new sites and for the assessment of landscape changes of wide archaeological areas in Ethiopia.     

Another (mud)brick in the wall: scientific analysis of Bronze Age earthen construction materials from East Crete

Mudbricks appear to have been one of the most common building materials used in domestic architecture in Bronze Age Crete. Well-preserved earthen construction materials from the sites of Vasiliki, Makrygialos and Mochlos in East Crete have been examined with regard to their macromorphological characteristics and their mineralogical and chemical composition in order to investigate the nature of the raw materials used, the technology of manufacture and the potential use of specific recipes. The methods applied include a combination of mineralogical and chemical analytical techniques, namely petrography, neutron activation (NAA), X-ray fluorescence (XRF), and X-ray diffraction (XRD) analysis. Finally, a range of raw materials from the immediate vicinity of each site were sampled and analyzed in order to compare with the archaeological data and identify potential sources. The analyses suggested that there is a degree of standardization in the recipes and the manufacturing process and that the selection of the raw materials depends on availability.     

Nari (calcrete) outcrop contribution to ancient agricultural terraces in the Southern Shephelah,Israel: insights from digital terrain analysis and a geoarchaeological field survey

A field survey revealed that Byzantine and Early Arab (ca. 5th to 8th century C.E.) agricultural systems in the semi-arid region of the Shephelah (central Israel) were similar to runoff agricultural systems in the arid region of the Negev (southern Israel). This similarity led to the hypothesis that systems in the Shephelah also function as runoff farms. This hypothesis is not trivial since runoff values in semi-arid regions are generally low due to intensive but short rainfall events, and due to the presence of sink patches that absorb runoff on slope surface. The aim of the current research is to examine whether runoff potential in a representative agricultural system in the Shephelah is sufficient for sustaining runoff farming. A geoarchaeological field survey and digital terrain analysis show that large Nari (calcrete) outcrops on the footslopes generate high runoff values that improve water potential. Hydrological simulations and calculations show that 230 mm of direct rainfall generates a water potential equivalent to 300 mm of direct rainfall. In view of these results, it is reasonable to conclude that the presence of Nari enabled runoff agricultural farming in the Shephelah region, even in drought years.     

A new perspective on Late Holocene social interaction in Northwest Alaska: results of a preliminary ceramic sourcing study

This research examines the evidence for prehistoric ceramic exchange networks over the last 2000 years in northwest Alaska through the use of neutron activation analysis of ceramic artifacts. Results from ceramic analysis on eight coastal and inland archaeological sites identified three source macrogroups and three associated subgroups. Clay source diversity and shared source macrogroups between geographically distant sites suggest the use of multiple sources and/or the movement of pots between production locales, mirroring related patterns in pottery stylistic data. Although additional analytical work is needed to fully understand the changing character of clay procurement and ceramic distribution across this time period, this study provides exploratory data on past ceramic production and distribution that hints at changes in exchange and territoriality in northwest Alaska during the late Holocene.     

Woodland period ceramic provenance and the exchange of Swift Creek Complicated Stamped vessels in the southeastern United States

Results of instrumental neutron activation analysis (INAA) of Middle and Late Woodland pottery (n = 313) and clay (n = 22) samples from northeastern Florida and southeastern Georgia are presented. Assemblages in this region include Swift Creek Complicated Stamped pottery that preserves unique evidence of social interactions through the inimitable qualities of designs stamped into vessel surfaces. Archaeologists have proffered various hypotheses to explain movement of ceramic vessels or the carved wooden paddles used in the manufacture of these vessels. This study tests these hypotheses and indicates that nonlocal vessels, particularly complicated stamped ones, were deposited almost exclusively in mortuary contexts, a pattern that requires new explanations for the role of pottery in social interactions. These data are being integrated with a larger project that aims to reveal the social processes that were tied to the manufacture, use, and distribution of pottery.     

Mapping prehistoric social fields on the Sepik coast of Papua New Guinea: ceramic compositional analysis using laser ablation-inductively coupled plasma-mass spectrometry

The Sepik coast of northern Papua New Guinea is one of the most linguistically diverse places on earth despite communities there currently being connected into wide-reaching social and economic networks that cross language boundaries. One possible explanation for observed human diversity is that social connections were substantially less intensive prior to colonial pacification. As a proxy for human interaction, we compositionally analyzed 287 ceramic sherds from archaeological contexts using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) to determine their place of production. Our results indicate that ceramics produced on Tumleo Island—currently the most important regional ceramic producer—were transported to other places on the Sepik coast after ∼1000 BP, suggesting that linguistic diversity on the coast has been maintained in an interactive environment for at least a millennium.     

Petrographic and geochemical analysis on the provenance of the Middle Bronze and Late Bronze/Early Iron Age ceramics from Didi Gora and Udabno I, Eastern Georgia

We report thin section petrographic and geochemical analysis of a total of 20 Middle Bronze, Late Bronze/Early Iron Age ceramics excavated from Didi Gora and Udabno I located in the Eastern part of the Republic of Georgia and 31 clay samples from eight different regions in the surrounding areas of the sites. The major and trace element compositions of the ceramics and clays were determined using a wavelength dispersive X-ray fluorescence technique. The results indicate that the ceramics were manufactured from local clays in Eastern Georgia, mainly from two local clays without any preference of one of the sources during the Middle Bronze, Late Bronze/Early Iron Age.