Alexandra Wysopal, MSHP '21
Fire-damaged stained glass can face a variety of condition concerns that complicates its conservation. Throughout the twentieth and twenty-first century, multiple approaches have been used to address the preservation of fire-damaged windows. What is included in a successful treatment plan depends on each unique object, the material involved, current condition, and future use. This report discusses the development, possible conditions, analysis techniques, and known treatment options for fire-damaged nineteenth to twentieth century American stained glass in order to provide a resource for developing a thorough approach to their conservation. A historic context of nineteenth to twentieth century American stained glass based on current research is established followed by a discussion on glass as a material with an emphasis on opalescent art glass. Approaches for identifying and assessing conditions using both optical and scanning electron microscopy are presented through a case study analysis. Available treatment options within the three categories of adhesives, plating, and a controlled environment are then reviewed. Finally, recommendations regarding how to develop a treatment plan and the need for future research are examined.
Section I. Materials and Technology in Use During the Stained Glass Revival
Section one contains a historical overview of stained glass created during the nineteenth and twentieth century. Topics covered included the components of stained glass, developments in design, manufacturing, and color and finishes.
Section II. The Characterization of Post-Industrial Glass Found in Stained Glass Windows
Section two covers the characteristics of glass, its chemical structure and composition, how glass is made, and issues facing fire-damaged stained glass. Types of deterioration discussed include degradation, crazing, and devitrification.
Section III. Approaches for the Identification of Conditions Present on Fire-damaged Opalescent Glass, A Case Study
Section three follows the documentation and assessment of a portion of a fire-damaged stained glass panel. First a historical background was established for the object, the object was photographed in reflected and transmitted light, and an annotated build pattern was created via AutoCad. Additional investigation was conducted using a stereomicrocope and scanning electron microscope.
Section IV. Review of Treatments for Fire-damaged Stained Glass
Section four reviews the three main treatment options for fire-damaged stained glass: consolidating, plating, and the use of a controlled environment. The cross-section diagrams included above illustrate how each treatment essentially operates. The dicussion of each treatment is broken down into the different materials, the pros and cons, and what conditions each treatment can realistically be expected to address.
Section V. Conclusions and Recommendations for Future Conservation Work and Research
Section five stresses the need for good documentation and how it is pivotal in guiding later restoration work should something happen to a window. The formulating a treatment plan subsection summarizes the documentation and analysis work performed in section three and how it can be applied to other works. The future research subsection lays out a survey plan to investigate how treated fire-damaged stained glass windows have survived in situ. This work is based on two previous studies, the ConstGlass project and the Protective Glazing Study.