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Daguerreotypes, nineteenth century photographs made entirely of metal, tarnish easily when exposed to atmosphere or other corrosive environments. The removal of such corrosion products has always been a controversial issue due to the irreversibility and potential damage inflicted by the treatment process. When performed using the proper technique and tools, electrochemical cleaning has been shown to remediate daguerreotype corrosion without causing damage to the object. This investigation explores in detail the effects of electrochemically treating daguerreotypes to better comprehend the physical, chemical, and aesthetic changes which occur during tarnish remediation. Such analysis includes understanding the extent to which tarnish is removed from the object, whether the microstructure and surface roughness are altered, and whether deposits are formed on the surface as the result of cleaning. Before characterizing the effects of treatment, a reliable and consistent electrochemical cleaning method was optimized on modern, custom-made daguerreotype coupons. These coupons were tarnished in controlled settings to create silver sulfide or silver oxide, two commonly found daguerreotype corrosion products. They were then treated by the optimized electrochemical cleaning process, which involved immersing the object in a 0.1 M NaNO3 electrolyte and connecting it to a platinum counter electrode, an Hg/Hg2SO4 reference electrode, and a potentiostat. Tests were executed to determine the most effective voltage for removing each corrosion product. Full characterization of the modern coupons was performed prior to corrosion, after corrosion, and after electrochemical remediation to provide full understanding of the treatment effects. Characterization techniques include scanning electron microscopy/energy dispersive x-ray spectroscopy, Raman spectroscopy, atomic force microscopy, x-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. The optimized process wa

The production of lead glaze paints has intrigued Southwestern archaeologists since the 1930s, and significant efforts have been dedicated to the study of this technology by researchers interested in the Pueblo IV (ca. 1275-1400 CE) glazes. In this dissertation I explore the technology of production of the earliest glaze paints produced in the Southwest: the Pueblo I (ca. 700-850 CE) glaze paints from the Upper San Juan. These glaze paints were produced nearly 500 years before the later and well studied Pueblo IV glaze paints, and these technologies represent two separate, independent instances of invention of glaze technology in the prehistoric Southwest. The unique aspect of prehistoric Southwestern glazes is that they were developed as paints, thus serving as decorations. Glaze paints are culturally and technologically significant because it is in the production of the paint that potters are innovating and experimenting with materials. This dissertation presents evidence for a patterned technological behavior in the production of Pueblo I glaze paints - while there is no evidence of specialization, there is evidence for shared technological knowledge regarding other aspects of production. The lack of control over the variability in visual appearance as related to the variability in compositions indicates that it is unlikely that any differences in composition represent intentional technological choices; therefore, Pueblo I potters were not using standardized recipes in the production of glaze paints. I argue that potters were aware of the effect of applying a lead-based paint to the ceramic, thus indicating intentionality, but could not control all of the variables that are involved in the production of a ceramic ware. To understand the mechanisms of invention, and later abandonment, of this technology, I looked for clues in the history of ceramic production in the area, and coupled it with a study of the social and environmental constraints placed on the product

The research presented in this dissertation covers three separate topics of conservation as defined by the National Science Foundation: 1) Materials Stabilization, Strengthening, Monitoring, and Repair; 2. Understanding Material Degradation and Aging; and 3) Materials and Structural Characterization of Cultural Heritage Objects (the `technical study'). The first topic is addressed through a study to assess the consolidant tetraethoxysilane for the stabilization of alum treated wood. Falling under materials degradation studies is a study published in American Museum Novitates to understand how environmental conditions affect the aging of fossil resins from five different deposits. Two separate studies are included in technical study of cultural heritage objects which comprises the third research area of materials characterization. The first is a survey of red dyes used in Chinese paintings from the Ming Dynasty to the Early Republic (1364-1911). The second is a study of the pigments, dyes and binders used in Hawaiian barkcloth (kapa) from the 19th century.

The characterization of biomolecules from ancient samples can shed otherwise unobtainable insights into the past. Despite the fundamental role of transcriptomal change in evolution, the potential of ancient RNA remains unexploited - perhaps due to dogma associated with the fragility of RNA. We hypothesize that seeds offer a plausible refuge for long-term RNA survival, due to the fundamental role of RNA during seed germination. Using RNA-Seq on cDNA synthesized from nucleic acid extracts, we validate this hypothesis through demonstration of partial transcriptomal recovery from two sources of ancient maize kernels. The results suggest that ancient seed transcriptomics may offer a powerful new tool with which to study plant domestication.

An investigation was conducted to show the number of American Indians in the field of conservation, through a quantitative and qualitative analysis. The research investigated the primary question, why are there so few American Indian conservators. In addition, the following secondary questions were examined: 1) How many conservators of American Indian ethnicity are there? 2) What factors influence the number of American Indian conservators? 3) How will American Indians qualified to practice conservation benefit museums? The findings for this study were collected through an online survey, personal interviews, and observations. The results showed that there was a significant relationship between education, conservation, and being American Indian. The study proved the hypothesis that there were not a lot of American Indian conservators. An earlier report investigating the status of American Indians in professional positions in museums nationwide revealed similar results (Rios-Bustamante, 1996). Other publications mentioned Indigenous people as collaborators and participants in various museum practices such as curatorial work, preservation, conservation, and exhibits; but did not specifically name an American Indian as a professional conservator (Bloomfield, 2013; Clavir, 2002; Erickson, 2002; Lonetree, 2012; Odegaard and Sadongei, 2005).A total of eleven participants were interviewed. Of the eleven participants interviewed, nine identified as American Indian from the United States, one identified as Maori from New Zealand working temporarily in the United States, and one as Italian-American (Table 13). Of the eleven interviewed, three identified as trained conservators qualified to practice conservation as a professional conservator. Of the three identifying at trained conservators, two were American Indian, Navajo/Assiniboine and Navajo. A total of ninety-three participants responded to the online survey. Univariate analysis using the standard t-test was used to compa

The mechanisms of the deterioration of cellulose acetate compounded with triphenyl phosphate were investigated. A key peak shift of 726cm⁻¹ to 718cm⁻¹ in the Raman spectrum of triphenyl phosphate (726cm-1 uncompounded) when compounded in cellulose acetate (718cm⁻¹) was tied to the action of C-O bonds in triphenyl phosphate. The molecular bonds responsible for the 726cm⁻¹ peak were identified by collecting and examining spectra of chemicals with functional groups similar to triphenyl phosphate. Initially it was hypothesized that triphenyl phosphate acts as nucleophilic catalyst of deacetylation. This mechanism was evaluated by dissolving triphenyl phosphate in solvents that served as functional group analogues of cellulose acetate. These liquid-solution systems have a faster rate of reaction and complete mixing with triphenyl phosphate compared with what is seen in cellulose acetate solid-solution systems. The results of the cellulose acetate analogue experiments did not support the hypothesis of triphenyl phosphate acting as a nucleophilic catalyst of deacetylation. The results instead support a new theory of deterioration induced by the recrystallization of triphenyl phosphate. Additionally, the prevailing theory of triphenyl phosphate induced deterioration as proposed by Shinagawa et al. in 1992 was reviewed. The experiments conducted here do not support Shinagawa's theory.

Detection and identification of pesticide residues on objects of cultural heritage is a serious and urgent challenge that currently faces many museums, Native American communities, and private collections worldwide. Organic artifact materials, such as wood, animal hide, basketry, textiles, paper, horn and bone, have traditionally been treated with pesticides to eradicate and prevent infestation by insects, rodents, and mold. These poisonous substances can persist for years in the controlled environment of a museum storeroom and present a potential poisoning risk to people who come in contact with the objects. Surface-enhanced Raman spectroscopy (SERS) has the potential to detect volatile organic pesticides in this context. The technique can overcome the insensitivity of normal Raman spectroscopy and fluorescence interference, and make possible detection of many organic compounds in parts per million concentration. This investigation is aimed at evaluating SERS for the detection and identification of volatiles in museums, with emphasis on naphthalene vapor. The potential of several SERS-active materials; Tollens mirrors, gold film over nanosphere arrays, citrate-stabilized colloidal silver, and nanoporous gold; to detect Rhodamine B and naphthalene is investigated. The research also highlights the mechanisms that underlie SERS, and the relationship between substrate nanostructure and SERS performance.

The application and use of non-destructive portable x-ray fluorescence (XRF) analysis is a critical tool in the preservation and interpretation of cultural material. Portable XRF instrumentation produce elemental compositional data that is used to reconstruct current artifact composition, which can be related to materials and methods of manufacture, technological practice, as well as object condition and presence of corrosion surfaces. Portable XRF analysis is used to assess a variety of material classes utilized in artifact manufacture. The dissertation research is based on a series of three case studies that represent typical groups of material culture commonly encountered in conservation and conservation science research.Conservators and conservation scientists frequently undertake analysis and interpretation of disparate groups of materials. Often, these objects are tied together by research questions or themes directed by outside influences including preservation issues requiring action; curatorial research interests; museum exhibition programs; as well as many other cultural heritage stakeholders. To this end, both non-destructive and destructive tools that provide measurements of interest play critical roles in analysis. The case studies have been designed to answer common compositional questions relating to (a) bulk analysis of Chinese coins, (b) characterization of Southwestern ceramic colorants, and, (c) chemical examination of post-depositional manganese dioxide accretions occurring on archaeological ceramic materials. They evaluate the value of data produced using effectiveness of non-destructive portable XRF analysis for the interpretation of archaeological materials. The case studies provide a template for the development of conservation science research, predicated on object preservation, which produce meaningful data for the interpretation and conservation of the analyzed archaeological artifacts. Portable XRF provides useful data that is used to suc

The beginnings of metallurgical activity have intrigued scholars for decades. In this dissertation, I explore early metallurgical activity on the Iranian Plateau represented by the evidence at Tal-i Iblis in southern Iran, and Seh Gabi and Godin Tepe in central northern Iran. Together, these sites offer a diachronic view of metal production on the Plateau as well as a view of metallurgical activities practiced at different scales of production. The metallurgical materials from Tal-i Iblis are firmly dated to the late 6th to early 5th millennia BCE, and this corpus includes hundreds of crucible fragments excavated from multiple trash dumps. Seh Gabi and Godin Tepe offer a smaller range of production materials from the 4th through 2nd millennia BCE, but they also include a large collection of finished metal objects. These later materials differ in style and process from the Iblis debris.Thorough examination of these artifacts, combined with comparison to a series of carefully controlled casting experiments, has returned numerous significant results. The metallurgy of the Iranian Plateau does not fit the standard model of early metallurgical development. The Iblis crucibles do not reflect an early "experimental" stage in copper production. Rather, these artifacts represent a carefully controlled, production process with a narrow range of variability in both temperature and reducing atmosphere. Further, there is clear evidence for the preference of arsenical-copper alloys at Tal-i Iblis. These ancient craftspeople sought high-quality ores from a source (the Talmessi copper deposit) over 500 km from their production facility.Metallurgical production on the Iranian Plateau is also characterized by the long-term use of crucibles as the primary reaction vessel well into the 2nd millennium BCE. There are some production centers on the Iranian Plateau that see the use of furnaces during the 3rd millennium, but crucible use persists at many sites. At Godin Tepe--a site with si

Recorded use of pesticides in the conservation of artifacts dates back to the 16th century. Museums today are faced with a tremendous task of identification and remediation of pesticides from artifacts in order to protect museum workers and the general public. In addition, artifacts are being repatriated by Native American tribes for use in cultural ceremonies which may subject the practitioner to health risks. Arsenic and mercury salts are among the pesticides that were used that are highly persistent and toxic. The primary challenge lies in removing these hazardous and persistent metals without damaging the materials or pigments on the objects.Concentrated aqueous alpha-lipoic acid solutions were developed for removing arsenic and mercury pesticides from materials commonly used in museum artifacts. The alpha-lipoic acid solutions were reduced using natural sunlight or laboratory ultraviolet lamps to enhance the binding of arsenic. The solubility of alpha-lipoic acid in various organic and inorganic solutions was determined and environmental parameters that impact the reduction and solubility, such as pH and temperature, were examined. The kinetics of the reaction of arsenic (III) with reduced lipoic acid was examined by varying the reduced lipoic acid, base and arsenic concentration as well as temperature and stirring conditions. The results indicated that the reaction occurs at a moderate rate primarily within 8 seconds in air. The reaction is chemically rate limited enhanced at higher temperatures and lower pH. Aerobic conditions significantly decreased the extent of the reaction with increased stirring rate. This impact was minimized by using a nitrogen environment or by limiting agitation during the reaction step.The methods developed were capable of removing up to 1000 µg/cm2 arsenic (of sodium arsenite) from simulated artifacts to levels near the lower detection limit of the X-ray Fluorescence Spectrometer (1 µg/cm2) without leaving detectable residues acc