Over 103 samples of stucco reliefs from the archaeological site of Palenque, Chiapas were studied by optical microscopy, scanning electron microscopy and X-ray diffractometry, in order to characterize the constituent materials and the techniques employed to make the lime plasters.

The results lead us to propose a sequence for the execution of the reliefs based on technological differences in the preparation of the plasters located in buildings belonging to different periods.

This paper explores the technology that Mayan artisans used in the preparation of the lime renderings for mural painting. The Mayan mixed lime with some kind of organic material, which presents amino acids in its composition.

Mortars from 16 different archaeological sites were analyzed by several analytical methods: optical microscopy followed by specific staining tests over cross sections, gas chromatography/mass spectroscopy and scanning electron microscopy. The first results pointed out that the use of an organic additive in the lime plasters′ substrates of mural paintings was a wide spread technology used in the Maya area -with some variations depending on the site location and its chronology. This finding suggested that the addition of such material would probably modify the mechanical resistance of the lime plaster substrates.

Digital image processing and numerical analysis of geophysical, geological and archaeological data from the ancient city of Teotihuacan have provided valuable information concerning the volume of structures, and the amount of materials removed from quarries. We have estimated the total area constructed as roofs, floors and walls in apartment compounds. This information has allowed the estimation of the total amount of lime plaster used in the construction of the city. This information supports new interpretations regarding the scale of resource utilization by this urban settlement.

Technical and analytical study of gold and tumbaga objects from Panama and Costa Rica, revealed the compositional range of gold-copper alloys used by the indigenous inhabitants. Using recent archaeological evidence for some of the chronology of goldworking in the area, the study examined metalwork from the Initial Period to the Veraguas-Gran Chiriqui style. From this study it is apparent that the variety of goldcopper alloys used for lost-wax casting did not undergo compositional change with time from the initial introduction of metallurgy to the area in the first century AD until the Spanish Conquest. Regional preferences may have existed in relation to the alloys chosen for particular images: for example Parita warrior figures were cast in gold rich alloys compared with frog pendants. Copper contents of the tumbaga alloys used extended from 5% to 50%, with gold contents usually above 45%, and with no addition of extraneous silver to the alloy. The silver content of many of the alloys studied from the area of Costa Rica was low in comparison with gold-copper alloys from the Colombian region.

Steatite ornaments have been found all along the different phases of occupation of the sites of Mehrgarh and Nausharo (Indus area) which range from about 7000 to 2000 BC. We show that the emergence of the first glazed beads goes back to the ancient Chalcolithic period (around 4000 BC) and that this use of glaze has undergone some changes during the following two millennia. For the moment we think that the changes that have been observed are only linked to a local evolution of the traditional glazing techniquess rather than to the existence of different workshops.

Analysis of eighteenth- and early nineteenth-century earthenware sherds found on the site of the Heyward-Washington House in Charleston, South Carolina has provided important clues concerning the manufacture, trade and use of a poorly understood tradition of African American pottery. These hand built, low-fired earthenwares, which archaeologists call colono wares, are abundant on archaeological sites, but they are virtually unknown in the historical record. Analyses included neutron activation analysis, xeroradiography, and petrographic analysis in addition to visual inspection. These data suggested that colono wares were transported to Charleston from rural plantations, where their manufacture was part of a widespread, informal cottage industry. The manufacture and use of this pottery appears to reflect the development of African American culture as a creole culture which drew upon a wide variety of traditions, reinventing and recombining these elements in ways designed to cope with the rigors of slavery.

A comparison of methods used for the manufacture of the largest ceramic storage vessels in two independent ceramic traditions over a period of centuries reveals distinctive trajectories in differing socioeconomic contexts. At Godin Tepe, a Bronze Age town in western Iran, an initially unique production sequence was gradually simplified and assimilated to the techniques used for the rest of the ceramic assemblage. At Gordion, an major urban center in Iron Age Turkey, the techniques changed relatively little over time. The degree and pace of change in production methods appear to reflect development of each ceramic assemblage as a whole and to relate to the scale and stability of the basic local economy.

Traditional western techniques for gilding of polychromed sculptures and panel paintings include the use of grounds prepared by the application of a first layer of gesso grosso followed by a gesso sottile layer, as described by Cennino Cennini in his treatise on painting techniques. These techniques were used in Italy since the middle ages, and were later adopted by many artists in the new world in the regions under Spanish and Portuguese (Brazil) rule, sometimes with local variations in materials and techniques.

This paper discuss the use of FT-IR spectrometry for the identification of inorganic materials present in the grounds of baroque wooden polychromed sculptures from Minas Gerais, Brazil. This technique allows the quantitative analysis of the separate layers of the grounds, with respect to the anhydrite/gypsum ratio present in the sample. The technique has several advantages over the one currently used (Debye-Scherrer chamber for powder X-Ray diffraction). FT-IR spectra can be obtained in a few minutes allowing quantitative results, while XRD usually takes more time and does not give accurate data for quantitative studies. The paper also discusses the results of the studies of the grounds in Brazilian polychromed sculptures and compares the original Italian technique with Portuguese and Spanish techniques and its variations in Brazil.

Typological and petrographic analyses of unglazed red earthenwares recovered from the archaeological site of Charles Towne on the Cape Fear in North Carolina reveal the presence of pottery imported from Barbados. These sherds suggest that a ceramic industry had developed in Barbados during the middle 17th century. Additional data reflect on the process of acculturation by which African (slave) potters working in Barbados created vessels of English design. A few sherds from Charles Towne suggest that in the absence of an established ceramic industry, African (slave) potters may have reverted to traditional methods of manufacture including coiling and open firing. This hypothesis is compared to data obtained in New England, Virginia, South Carolina, Jamaica, and Barbados to refine the concept of acculturation as evidenced in vernacular ceramic manufacture.

Archaeological investigation of early Colonial Period orange micaceous earthenware from eastern North American sites is complicated by the presence of a variety of material that may have either local, European or Barbadian ancestry. The ephemeral Charles Towne colony (1664-1667) on the Cape Fear River in southeastern North Carolina is currently under historical and archaeological investigation by the University of North Carolina at Wilmington. At this site approximately 20 to 25% of the recovered sherds are of an orange micaceous composition. The provenance of these sherds is being investigated by a combination of petrographic techniques and clay and detrital mineral studies. We use this approach to evaluate whether these sherds represent evidence of local manufacture. To this end we have studied the local clay deposits as possible source areas and acquired samples of both sherd and clay material from Barbados for comparison. Results from this study have implications for early Colonial local earthenware manufacture and points to the influence of Barbados in the colonization of eastern North America.

The application of provenience analysis to the delineation of zones of economic interaction is considered for the Middle Bronze IIa period in the southern Levant. Preliminary petrographic analysis of ceramic finds from Tel Nami, a small port with substantial East Mediterranean contacts, is consistent with local coastal production, with possible utilization of nearby igneous sources. The petrography of storage jars containing imported Aegean legumes is consistent with local typology and geology.

Neutron activation analysis of metal-rubbing samples from over 500 silver and gold bars and coins resulted in data for the silver, copper, and gold contents of the objects. The analysis of gold coins (from a 1715 shipwreck) minted in Bogota also showed detectable levels of the metal iridium (>0.002%) whereas gold coins from other mints did not. The presence of detectable iridium, therefore, might serve as a diagnostic indicator of early 18th century gold of Colombian origin. Data are also given for silver and gold ingots from a (ca. 1520s) shipwreck off the coast of the Bahamas and for silver bars from the 1622 Atocha shipwreck.

Neutron activation analysis of microgram metal-rubbing samples from over 2,000 Sasanian (Persia: 224-651 AD) silver coins and a few hundred art objects allow grouping the data in terms of the gold-impurity levels. About 1,000 of the silver coins were from the reign of Khusrau ∥ (591-628 AD) and represent various mints and dates. For the early coins, mg gold/100 silver values of less than 0.3 are associated with relatively modern fakes. The authentic coins and authentic silver Sasanian art almost always have values in the range of 0.3-1.0. Questionable ‘Sasanian’ art objects in private collections usually have goldimpurity levels of less than 0.3.

Chemical analyses and polished section studies have been made on selected artefacts from the period 1 to 400 AD found in Scandinavia. By means of a multielement method used on 2 - 4 milligram solid sample (OES), the copper alloys are found to be quite characteristic for various groups of artefact. The trace elements underline systematic differences in form and age whithin the same stylistic type produced over a long period. The workshops seem to have had their own tradition for using different alloys for various parts of a specific artefact. The fact that the same type of artefact is produced in bronze as well as brass, probably indicates a different origin. Based on these results analyses have been started on a few available ingots and ore minerals in the attempt to trace the provenance of Scandinavian artefacts.

Identifying the sources of metal supply and reconstructing the routes of metal trade in the Eastern Mediterranean during the Bronze Age, in the 3rd and 2nd millennium B.C., depend from the complementary evidence provided by sources belonging to various fields of scientific research. Prominent among them are the study of the ore deposits and their periods of exploitation, the analysis of artefacts (provenance studies), the interpretation of ancient texts and the excavation of wrecked ships carrying metal ingots, with inventory and dating of their cargo. The paper proposes to review those aspects, in relation to copper, tin, silver and gold. Its aim is not to provide a systematic and comprehensive catalogue of all the available data. This has been done in the recent years, lastly by H.-G. Buchholz in a detailed article Der Metallhandel des Zweiten Jahrtausends im Mittelmeerraum1. The purpose will be rather to have a general overview of the most significant evidence, especially as far as the prehistoric Aegean is concerned: the results of field research in the area of the Lavrion mines in Attica, lead isotope analyses of bronze objects excavated in the Aegean, the archives from Mari and Ugarit, giving reference to international transactions about metals, and the Ulu Burun and Cape Gelidonya shipwrecks. The general picture that emerges from the review allows a better understanding of the relations between the different areas of the Eastern Mediterranean that appear to be closely connected with pressing material necessities and conditions and not only with cultural intercourse and exchange.

Characterization of materials by methods which require neither expensive equipment nor specialist participation are of interest to archaeologists, conservators and other researchers who work in the field. Utilizing as points of focus those questions cited most frequently in a survey of field conservators, archaeologists and related literature sources, tests are reported which may be used on site to characterize artifacts, their condition and the context from which they come, to monitor the progress of treatments and to assess the stability of materials for use in longterm storage of archaeological collections.

Little is known about the colorants that were used in Aztec manuscript illumination. The study of contemporary sources may give us useful information. The Florentine Codex gives names and descriptions for colorants that were traditionally used by the Aztec scribes. These descriptions allow us to identify the botanical source of some of these colorants.

The identification of the original plant materials made it possible to come to a reliable reconstruction of the colours. The colorants that come from plants show a large variation of chromophores and may belong to the flavonoids, the carotenoids, or the anthocyanins.

The chemical constitutions of some of these colorants and the possible methods for their identification are discussed.

Tenacity of slip adherence on MM II and LM IB pottery is investigated using the SEM. Results indicate that the degree of adherence is due to an advanced vitrification which causes a glassy interface to form between the slip and the fabric of vessels. Superior adherence, moreover, is related to the darkness of the final slip color, which generally is closer to black on MM II vessels.

The dark-firing slips used for Minoan pottery have never been adequately characterized, and opinion has been divided on whether or not the slips are made from the same material as the fabrics. A program of analysis by PIXE was carried out at the Bartol Research Institute, University of Delaware, on MM and LM I sherds from east Crete, analyzing both the slips and the fabrics. The results indicate several compositional variations including a consistently higher percentage of K in the slips. A consistently high percentage of Ca is in the fabrics, but the concentration of Ca in the slips is variable. Probably different materials were used for fabrics and slips, and although the clay source may have changed between Middle Minoan and Late Minoan I, the materials remained generally constant in LM I in spite of a change to a different firing technology resulting in browner slips.

The purpose of this study was to characterize the materials and methods of manufacture of a lead-tin and luster glazed earthenware deep dish formerly in the collection of William Randolph Hearst and currently at the Walters Art Gallery in Baltimore, MD. A number of analytical techniques were employed in order the evaluate the authenticity of the piece: stereomicroscopy. Xeroradiography. polarized light microscopy, scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), thermoluminescence analysis (TL). and neutron activation analysis (NAA). The research results support stylistic evidence in affirming that the object is a 16th century Valencian product.