Scanning electron microscopy and energy dispersive x-ray spectrometry (SEM-EDS) has been employed along with the light microscope to describe some metal threads taken from some late Medieval and Renaissance textiles attributed to Italy in the collection of the Metropolitan Museum of Art, New York. Comparisons are made within the group studied and to those descriptions of metal threads found in recent literature. The results are discussed in terms of geographic and historic markers of the metal thread technology employed.

We have used the TRIGA reactor and the Ion Beam Facility at Cornell to illustrate neutron induced autoradiography and PIXE analysis of known pigments in demonstration paintings made for our undergraduate course, ‘Art, Isotopes and Analysis’. A group of pigments were chosen containing elements with half-lives detectable by the neutron activation process. The pigments (suspended in a binding medium of linseed oil) were first painted on test swatches of acetate and their characteristic x-ray lines measured with a 5 Mev beam of protons directed through a thin Kapton film for external (in air) analysis (PIXE).

Three layers of images, each painted with a different pigment, overlay one another. The painting is then taken to the TRIGA reactor for neutron activation. After activation, the painting is placed in contact with sheets of Polaroid type AR positive transparency film at different times after exposure. The gamma spectra during the sequence are also measured to provide identification of the ‘active’ isotopes during each film exposure.

Stone statuettes from turkey in simply shaped animal and bird forms were analyzed using scanning electron microscopy. observations made in drill holes in some of the artifacts led to definite unequivocal evidence for forgery while others were equivocal.

This study examines the methods for determining the effects of temperature and relative humidity (RH) on the dimensional and mechanical properties of artists' materials. Using both of these properties, typical cultural objects, such as paintings and photographs can be modeled on the computer to correlate the magnitude of developed stresses to environmental changes. Comparing these calculated stresses with the measured strength of the materials provides the opportunity to assess the potential risk from damage due to environmental change. Recognizing that the mechanical properties of polymeric materials are functions of the rate of the application of load, the time they are subjected to a load, the temperature and the relative humidity, it becomes a question of identifying those parameters that are the most important in determining the correct information needed for computer modeling.

The mechanical properties of strength, modulus, and elongation to break were studied for artists' acrylic and alkyd paints under varying conditions of temperature and relative humidity (RH). In the ambient environment, 23° C, 50% RH, acrylic paints are very flexible and are able to sustain large deformations (>50%). Alkyd paints are much stiffer and stronger, and they cannot sustain deformations nearly as dramatic as the acrylics. Acrylic paints at 5% RH are stiffer and stronger than at 50% RH and their ability to stretch is lessened. At temperatures below 15° C at 50% RH, the strength and stiffness of acrylic paints begin to rise rapidly. Some were found to be brittle at 5° C, and by −3° C, all were brittle. At a lower RH, some acrylic paints became brittle at a temperature near 11° C. These temperatures and relative humidities may be found in the transport environment of art objects, and may render them subject to possible damage.

The possibility of using air-coupled ultrasound to find delaminations between layers in paintings was investigated. Simulations of modern paintings were constructed with hardboard as the support layer, and a layer of gesso, an animal hide glue and chalk, as the upper layer. Delaminations were introduced between the two layers. Scanning the samples using air-coupled ultrasound clearly showed these flaws. A transmitting transducer, which was 25 mm in diameter and had a focal length of 51 mm, was placed 11 mm from the back surface of the sample and an identical receiving transducer was placed 51 mm from the front surface. The transducers were operated in a tone burst mode at a center frequency of 475 kHz. Signal enhancement techniques were used to improve the contrast of the data.

Modern transparent papers, also known as tracing papers, require specific chemical and physical properties, such as translucency, smoothness, and whiteness, which are produced by specially formulated compositions and manufacturing procedures. Ironically, these special formulations may in some ways render such papers susceptible to problems from damage and degradation, while also making them particularly reactive to moisture and solvents that must be used in conservation treatments to correct these problems. In order to evaluate the effects of water and organic solvents on such papers, four research projects were designed to consider the variables of paper composition, properties, type of solvent, technique of application of solvent, and flattening. This paper summarizes findings on materials characterization, degradative effects of aging, and some effects of solvents used on transparent papers for stain reduction, humidification, and flattening.

Through a series of experiments the mechanical properties of paper are explored. Hydrogen bonding is fundamental to the performance of paper and its disruption results in distinctive stress-strain behavior. Stress-strain curves were generated from which tensile strength, Young's modulus, percent stretch, and work (tensile energy absorption) were obtained.

It was found that the contribution of the fiber to the mechanical properties of paper is primarily elastic. Fibers are many times stronger than paper. Only fibers which have been severely deteriorated show measurable changes in stress-strain behavior. Fiber deterioration results in characteristically different stress-strain behavior than that which results from disruption of interfiber bonding.

Water immersion results in the disruption of interfiber bonds in paper, leaving only 2-3% of dry tensile strength. Interfiber bonds make a profound contribution to the mechanical properties of the paper. Aqueous treatment is shown to be a radical treatment, altering the original dried-in properties of the sheet. The release of structural bonds and dried-in strains during wetting and the subsequent reformation of interfiber bonds during drying are shown to be independent of water purity, be it ultrapure water, tap water, or water containing washing aids such as Ca(OH)2, NaOH, CaCO3 or Na2CO3.

The effects of immersion in organic solvents was explored. Solvents have effects on mechanical properties which are approximately proportional to the degree of swelling caused by the solvent. Water, the liquid which caused the greatest swelling of the liquids evaluated, is shown to be the most disruptive liquid followed by methanol and acetone; toluene caused virtually no change.

To explore the behavior of interfiber bonds paper was taken through a solvent exchange process. A sample was immersed in water and then taken through separate ethanol and acetone immersions to toluene, and dried. The result was a sheet with little bonding and decreases in all mechanical properties. To explore the surface tension and capillary action effects of water, the solvent-exchanged sheet was re-immersed in water. Upon drying, interfiber bonding was reintroduced which resulted in the regain of mechanical properties lost.

A paradigm for the mechanical behavior of paper is developed. Fibers contribute elastic behavior and interfiber bonds are a principal source of plastic behavior.

The effects of drying on paper after water immersion are explored by evaluating mechanical properties. When paper is wet, structural interfiber hydrogen bonds are disrupted; drying reverses this process. However, some “as manufactured” mechanical properties are lost after wetting and drying. The method of drying was found to be critical for regaining the mechanical properties of a dried sheet.

The effects of (1) wet-pressing (weight on paper during drying) and (2) wet-straining during drying are assessed. Application of incremental increases of the two variables results in changes of the mechanical properties which eventally reach and exceed the original mechanical properties which are lost during standard water immersion and drying treatments.

The treatment method which most closely reproduces the “as manufactured” properties involves wet-pressing and wet-stretching. In particular, friction stretch-drying in an air-bag press can approximate original drying conditions. However, alterations of optical properties of the paper and design media due to elevated pressure prevents endorsement of the methodology.

The diffusion constants of sulfur dioxide in boxboards, commonly used to store archival documents, have been measured. For the most common boxes used by National Archives and Record Administration a diffusion constant of about 0.001 cm2 / sec was determined independent of gas concentration. These results are discussed in terms of a model of the microenvironment provided by these boxboards as used in archival storage.

Hygrometric half-lives and air exchange rates of four commonly used types of museum cases: Solander boxes, portfolio boxes, music boxes, and document boxes were measured. This paper will present the experimental results and illustrate the effect of the construction materials and closure characteristics on the moisture buffering capability of museum cases.

The accelerated aging of unplasticized Cellophane film specimens was conducted at tempe:atures ranging from 80 to 150 °C in a dry, forced-air convection oven for various periods of time. Colorimetric evaluation showed increasing discoloration which could be partially reversed by rinsing in deionized water. The infrared spectra of samples aged within this temperature range show the same changes, dependent upon aging time. This indicates that the species formed in the films at temperatures above and below the boiling point of water are the same, and that the moisture content of the films may affect the reaction rate, but not the mechanisms. The observed data in the visible region fit the standard pseudofirst-order kinetics model and are in excellent agreement with those determined for both the color change of cotton and the UV absorbance of Cellophane under similar conditions.

Analyses of the distribution and nature of abrasion on ceramic rings from the third millennium B.C. portion of the Godin III pottery assemblage in western Iran (2600-1400 B.C.) indicate that it represents use wear. Residual scars on pottery vessels and reconstruction of vessel forming sequences support identification of these rings as potter's tools. They provide interconnections among varied sizes of Buff Common ware vessels made using different forming and finishing methods. This strengthens the inference of workshop production by specialist potters who make the full range of Buff Common ware vessels.

Drilling technology of the Indus Valley Tradition was highly specialized and various types of chert and jasper were used to drill different types of materials. Earlier studies used primarily macroscopic observations to define features such as the manufacturing technique of drills, the raw materials and the mechanics of drilling. These generalizations can be revised given the discovery of important workshop areas and the availability of SEM, XRD and electron microprobe analysis. This paper will summarize the current state of. drilling research and define two categories of drills that were used in antiquity; tapered cylindrical drills and constricted cylindrical drills. Directions for future research on the relationship between drilling and other contemporaneous technologies are discussed.

The probable composition of a weathered, blue-green glaze on a ground quartz bead was reconstructed. The bead was excavated from Operation 5 at Tell es-Sweyhat, Syria, in 1991 and is dated to the last quarter of the third millennium B.C. Special sample handling was required by the poor state of preservation of the glaze. Microprobe analyses and replicate melts showed that the composition was 60% SiO2, 20% CuO and 20% flux, probably as soda, potassia or a combination. This composition is unusual for ancient glasses and glazes because of its high copper oxide content, which may indicate a link with copper or malachite technology. Very few glass and glaze compositions are known from the third millennium B.C., and none of these has such a high copper concentration, nor are there examples reported from the mid-second millennium B.C. with one exception of glazed tiles from Kerma in Sudan. This rare and unusual composition suggests that there may have been several paths to the development of glasses and glazes. Some of these paths were successful, and some others, as this one, did not continue and were “dead-end” technologies.

In the beginning of the second millennium B.C. Babylon became the centre of power in Mesopotamia. Hammurapi (1792-1750 B.C.) was one of the most important kings of the First Dynasty of Babylon. He is above all known for his law code (Codex Hammurapi). At the height of his power the Old Babylonian Empire extended as far as Sumer in the south and to Nineveh in the north. After the Old Babylonian times a dark period followed in the history of Mesopotamia. The conquest of Babylon in 1595 B.C. by the Hittite king Mursilis I ended the First Dynasty of Babylon. His allies, the Kassites from the Zagros Mountains, occupied Babylon without breaking the Babylonian traditions. Dur Kurigalzu became their capital. In 1157 B.C. the Kassite Dynasty was attacked from Elam (southwestern Iran) and came to an end.

Ceramic remains of fragmentary vessels, believed to be smelting crucibles based on microscopic field investigation, were analyzed using a variety of techniques in order identify the metal being processed and to reconstruct the ancient processing, especially ranges of composition, temperature, atmosphere, and the constraints on processing which each of these processing variables would have imposed. The identification of the metal being processed in the crucible surface residues and the slags provide data to resolve a dispute over the nature of the ancient metallurgical processing at Goltepe; gold and iron have been suggested as alternate metals but were not found. Intensive study of the ceramic and slag microstructure, composition and thermal history was required to establish the processing constraints which will be used to aid future replicative smelting experiments at the site.

The chemical compositions and firing temperatures of seventy-four stamped pottery and proto-porcelain fragments which were excavated from Jiangxi, Zhejiang, Henan and Fujian were studied. Their chemical compositions, together with a database of more than 600 pottery and porcelain bodies and 100 protoporcelain and porcelain glazes previously investigated, were processed and evaluated by correspondence analysis. Their firing temperatures and those of more than 200 pottery and porcelain samples were compared as well. The results of this investigation yield a more objective and comprehensive view of the process of technological evolution of ancient Chinese pottery and porcelain than heretofore possible. The place of stamped pottery and proto-porcelain in the evolution process is better understood, and the differences between the patterns of continuity and change in the north and the south of China is further discussed in this paper.

A series of pottery fragments from an early Neolithic site in Iran is analyzed to determire the original baking temperatures. Two magnetic techniques are used: remanent magnetization decay, and hysteresis loop analysis. The results are complementary, although some are, at first sight, contradictory. The causes of these apparent contradictions are explained. The analyses confirm that the pottery was baked under highly variable conditions, probably over open fires. Control of baking was poor, and there was considerable variability not only from one vessel to another but even from one zone to another on the same vessel. Our results suggest the need for caution in interpreting often ambiguous findings in this field of ancient technology.

At the Neolithic archaeological site at Liangzhu in China, located 16 kilometers northwest of Hangchou in Cheking province, many objects of stone, jade, and black pottery were discovered between 1936 and 1939. While the exact date of the Liangzhu culture is uncertain, it is considered to be between 3500 and 2000 BC. A characteristic feature of the Liangzhu-culture pottery is a thin black finish and a layered structure of the body consisting of a black core sharply changing to a gray or red band ending in the black surface.

The focus of this paper is to explain why the cores of the vessels are black and why the colored bands occur and what they indicate about the firing conditions of the pottery. Analyses were ca rried out using SEM, electron-beam microprobe, X-ray diffraction, photo-electron spectroscopy, and polarizing microscopy. From this evidence, it is clear thait a clay vessel containing abundant charcoal was thrown on the wheel and then fired under reducing conditions so that charcoal was retained and iron reduced. Just before completion of the firing or during the cooling phase, air was allowed to enter the kiln and a limited thickness of the outer core was oxidized. Then, for decorative purposes, the surface was heavily smoked, and/or a thin iron-containing slip layer was reduced in smoke and burnished.