A recent visual survey of Abstract Expressionist-era paintings in the collection of the Hirshhorn Museum and Sculpture Garden (HMSG), Smithsonian Institution revealed a particular type of paint layer separation. Earlier work by the authors showed that zinc oxide in oil paint is a contributing factor to the problem. Ten samples from five Abstract Expressionist-era paintings as well as twenty-three samples eight years or older from the Smithsonian Institution’s (SI) Materials Study Collection were analyzed by pyrolysis – gas chromatography – mass spectrometry (Py-GC-MS), and unexpectedly significant amounts of oleic (cis-octadecenoic) acid were detected in samples containing high proportions of zinc oxide (25 % or greater by weight). In a typical fully cured oil paint, the oleic acid is oxidized to azelaic (nonanedioic) acid. Although the formation of zinc soaps in oil paints is well-known, the detection of zinc oleate in paints by Py-GC-MS has never been described. The close-packing of the oleate chains in the plate-like structure of zinc oleate prevents the oxidation of the cis-double bond, and therefore prevents the formation of azelaic acid. The detection of zinc oleate in paintings is an indication that the paint layers are at risk for future separation.

Native American quillwork is well documented in art historical and anthropological literature. Methods for folding quills to create floral and abstract designs are addressed, but studies of the materials used to color the quills are conspicuously absent. This is particularly true for the pre-aniline dyes used by communities east of the Mississippi, as historical recipes tend to be more reflective of Plains and Pacific Northwest quillwork traditions. Research to derive quill dye baths from raw materials has and continues to be pursued, but no large-scale scientific analysis of existing quillwork has previously been undertaken. To address this literature gap, a liquid chromatography-mass spectrometry analysis project has been completed on early quillwork in the collections of the McCord Museum, the National Museum of the American Indian, and the Peabody Museum of Archaeology and Ethnology; reflectance spectroscopy and X-ray fluorescence were also used as complementary techniques and to investigate the use of metal salts as quill stains. An extensive literature review provides a historical understanding of pre-1856 quillwork dyes; this representation will be compared with the usage patterns suggested by the collections’ analysis. A more complete understanding of Native dye technology, addressing assumptions currently made with regards to the use of mordants, mixing of multiple dyestuffs in a single bath, and incorporation of “Old World” dyes, will also be presented.

Large amounts of bronze weapons have been unearthed from the pits of the Terracotta Warriors. Though they are of the same period, their condition is quite different; some are slightly corroded; some have almost no corrosion with a gray-black or green-gray surface; some are badly corroded. ICP, XRD, SEM, EDX, XRF, AES and Metalloscope were employed on seven bronze weapons to investigate their composition, structure and differences between the surfaces and bulk metals. Results showed that all these bronze weapons are high-tin bronzes. The three bronze swords contain a higher tin content than the others and have undergone heat treatment, which gives them the necessary tenacity of weapons. The surface layers of the weapons are rich in tin in various degrees because of selective corrosion and the migration of copper ions during corrosion. Some objects are more corrosion-resistant by a quenching treatment and the formation of compact tin oxides.

This paper describes the five-year Lightfastness Correlation Project that I am conducting in sixteen institutions in the US and Western Europe, with the support of the Samuel H. Kress Foundation.

Dr. Robert L. Feller, a scientist at the National Gallery of Art, published several papers in the 1970s in which he speculated that a certain duration of time could be correlated, in a general way, to the color changes noted in the Blue Wool Textile Fading Cards. Museums use the cards as inexpensive dosimeters, put somewhere in a gallery along with the art. Enough is known about their behavior to have confidence in their ability to indicate when it is time to remove an object from exhibition.

The Blue Wools are also used in two Standards developed by ASTM International’s Subcommittee D01.57 on Artists’ Paints and Related Materials. ASTM D 5383 and ASTM D 5398 are simple lightfastness test methods. In them, the Blue Wool cards are exposed to natural daylight along with any colored material, and are used to tell the artist when it’s time to stop the test and as a rating device.

Another ASTM Standard from D01.57, ASTM D4303, uses instruments to control the accumulated amount of natural daylight, or simulated daylight in a xenon arc light exposure machine. It also uses a spectrophotometer to calculate the color change that can occur in a test sample, expressed in CIE L*a*b*. There is also a standard formula for calculating color change that results in a single number, expressed as Delta E, or ∆E.

The ∆E number is used by ASTM D01.57 to assign lightfastness ratings to artists’ coloring materials covered by its Specifications for various products. Initial development of the ASTM methods began in 1977; we have 33 years of data that confirms the worth of the methods used in our testing.

What is the relationship between the results of Blue Wool testing and the results using D01.57’s technical ∆Es? This is a fundamental question we have yet to thoroughly examine. We have begun to work on the problem, using accelerated natural and artificial light sources as in ASTM D 4303. But no one has ever tried to compare the results of these two test methods in a museum environment, over an extended period of real time.

“The Lightfastness Correlation Project” ends in August 2011, and a final scientific report will be submitted to the sponsor, The Samuel H. Kress Foundation, in September 2011.

Portugal is ranked within the 10 countries with the most dinosaur taxa and the Lourinhã Formation is known by the Late Jurassic findings of dinosaurs and other fossils. In many cases, studies of the external morphological characteristics of the fossils are not sufficient to extract all the information for a paleontological study and, thus, observations of internal structures, using non-destructive techniques, are required. The fossils studied in the present work belong to the Museum of Lourinhã. The access to the Geesthacht Neutron Facility in Germany allowed us to characterize a jaw of the dinosaur Baryonyx walkeri specimen and the jaw of a crocodile (possibly a Tomistomidae) by Neutron Tomography. The study allowed us to detect the presence of teeth inside the jaws and it provides valuable information about the development of its dental characteristics. Synchrotron radiation based micro-computed tomography studies on tiny samples have been performed at the beamline HARWI II operated by the Helmholtz-Zentrum Geesthacht at the storage ring DORIS III at the Deutsches Elektronen–Synchrotron DESY in Hamburg, Germany. The first data recorded for eggshells collected in the Lourinhã Formation is shown. It allowed us to visualize the morphology of the pores and their connectivity in the eggshells, providing information that is either exceedingly difficult or impossible to obtain by traditional methods based on section cutting.

The Cultural Heritage Science (CHS, formerly SCIART) Program seeks to enhance opportunities for chemistry and materials research at the interface between science and art. The objective is to promote collaboration between cultural heritage scientists, mainly located in US museums and chemists and/or materials scientists in US academic institutions to address grand challenges in the science of cultural heritage. Through the first competition, eight projects, two to three years in duration, were funded at $270,000 to 495,000 each. Every successful proposal demonstrated a clear need for collaboration with good synergy between the collaborating groups, and provided plans for meaningful training experiences for students and/or postdoctoral researchers in the field of cultural heritage science. It is anticipated that the CHS Program will continue for two additional years in a similar fashion. During this period, researchers should be able to more easily identify the disciplinary programs in materials research or chemistry relevant to their work, and their proposals will be reviewed together in panels. Proposals falling outside of the CHS specifications may be submitted directly to the relevant program/s of interest at the National Science Foundation (NSF) as unsolicited proposals. After the CHS Program ends, unsolicited proposals will remain the key mechanism for obtaining NSF funding in this research area.

Metallography, chemical analysis, and microhardness testing of copper-alloy objects from Anau, Turkmenistan (c. 3000-2400 B.C.), were undertaken to determine how technological choices influenced the properties of the finished objects. Additionally, this analytical program assessed the position of the Anau metals in the development of metallurgy in southern Central Asia. Metallographic analysis of three bladed objects, all copper-arsenic alloys with 1% to 5% arsenic, showed that their edges had been cold-worked to a greater or lesser degree to create a blade that maintained a sharp edge, but also had flexibility to withstand impacts. Microhardness testing confirmed that the blade edges had a higher hardness than the interior metal. One of the objects had sulfur-rich inclusions in the metal matrix, suggesting the original charge had at least some sulfide ore. Conversely, a curved rod, made from a copper-lead-tin alloy, was cast to shape and showed no additional working of the metal. Lead, visible as black particles in the microstructure, was likely added to make the molten metal flow more easily. The metallographic and chemical analyses showed that the Anau objects fit into the tradition of Southern Central Asian metallurgy, though the presence of tin in objects of this period is more rare here than in later periods. Anau smiths displayed an ability to manipulate both physical and chemical properties of metal in order to produce functional objects with optimal characteristics.

Scholars have tried to link the dramatic rise of iron production in the Near East during the Early Iron Age with changes to the political landscape that occurred at the end of the Late Bronze Age. These attempts have been hindered by a lack of excavated iron production contexts dating to the Early Iron Age. The recent discovery of an Early Iron Age metal workshop at the site of Tell Tayinat, Turkey, provides an opportunity to reexamine some previous assumptions. Preliminary chemical analysis of metal and slag samples indicates that during the 12th century BC iron- and bronze-working were not separate, specialized industries. Instead, production of both materials took place within the same workshop context. Furthermore, this work highlights the importance of prestige goods in the Early Iron Age repertoire.

The aim of this paper is to focus attention on some current developments in the physical examination of decorative ceramic thin coatings performed in France and in Europe. Thanks to the recent progress in instrumentation and the implication of material science teams, significant new results were obtained concerning the finishing coatings of ceramic ware, and specially regarding the luster decorations of Islamic medieval potteries and the high gloss coatings of Greek and Roman ceramics.

Silver jewelry and repoussé work have been a significant part of the material culture of Tibet for centuries. While objects such as offering bowls, skullcups, butter lamps, ewers, portable shrines and incense burners serve religious purposes, many other type of objects are important in the secular life of Tibetans. This secular silver material culture includes items such as necklaces, bracelets, rings, hair ornaments, amulet cases, vessels, belts or waistbands and hooks for milk pails or butter churners.

The discussion presented here focuses on secular silver objects made in the workshop of a traditional Tibetan silversmith in the town of Songpan in northwestern Sichuan Province, China (traditionally comprising part of eastern Tibet). With interruptions in traditional practices during the Cultural Revolution, the question has been raised about whether or not such practices have continued [1]. This research is part of an effort to document traditional Tibetan craft practices and identify threats to their preservation. Workshop processes start with the craftsman acquiring the silver, making or buying tools, arranging the work area, and the customer commissioning a piece. Technical processes include working the silver ingot to form an object, annealing and quenching, making silver wire, filigree, granulation, soldering, inlay work, pickling and finishing.

Some changes have been introduced in how the workshop operates during the lifetime of the current craftsman, leading to differences between his procedures and that of his father, under whom he apprenticed. Some of these changes are due to technological advances (new equipment becoming available) and some are due to larger societal changes (for example, new government regulations regarding purchasing of raw silver). These changes are often in technological style affecting the fabrication stages, but not necessarily visible in completed objects, which retain their traditional forms, visual style and functions.

Yungang Grottoes in Shanxi, China, which represent outstanding example of Chinese outdoor immovable stone artifacts, are precious world cultural heritage. In the present study, the preparation and assessment of superhydrophobic hybrid coatings with photocatalytic activity on the sandstone substrate collected from Yungang were explored preliminarily. The protection efficiency of coating is investigated by measuring the water-stone contact angles, water vapor permeability, water absorption, and resistance to acid and salt corrosion. Results show that the superhydrophobic organic-inorganic hybrid coatings with photocatalytic and self-cleaning properties are highly suitable for the conservation of stone monuments.