Dating and Documenting Historic Leaded Glass

A typical Tiffany-style window includes opalescent glass, intricate leading, copper foil, extensive etching, plating, and a scene with perspective that simulates a painting. Photo: Neal A. Vogel.

Before deciding on any treatment for historic leaded glass, every effort should be made to understand-and to record-its history and composition. Documentation is strongly encouraged for significant windows and other elements. Assigning an accurate date, maker, and style to a stained glass window often requires extensive research and professional help. A documentation and recording project, however, is worth the effort and expense, as insurance against accidents, vandalism, fire and other disasters. The better the information available, the better the restoration can be. The following sources offer some guidelines for dating leaded windows.

Building Context. The history of the building can provide ready clues to the history of its leaded windows, doors, and other elements. The construction date, and dates of major additions and alterations, should be ascertained. Later building campaigns may have been a time for reglazing. This is especially the case with churches and temples. They were often built with openings glazed with clear leaded glass. Stained glass was added later as finances allowed. Conversely, the windows may be earlier than the building. They may have been removed from one structure and installed in another (once again, this is more likely with religious structures). Bills, inventories, and other written documents often give clues to the date and composition of leaded glass. Religious congregations, fraternal lodges, and other organizations may have written histories that can aid a researcher.

Many studios and artists "signed" their work or affixed signature plates. Signatures sometimes include the date. This information can help authenticate a window. Photo: Neal A. Vogel.

Inscriptions and Signatures. Many studios and artists affixed signature plates to their work-often at the lower right hand corner. In the case of Tiffany windows, the signature evolved through several distinct phases, and helps date the piece within a few years: Tiffany Glass Company (1886-1892), Tiffany Glass & Decorating Company (with address, 1892-1902), Tiffany Studios New York or Louis C. Tiffany (post 1902). (Tiffany Studios, like others, did not always sign pieces and the absence of an inscription cannot be used to rule out a particular studio or artist.) Windows may feature dated plaques commemorating a donor. However, these do not always indicate the date of the window, since windows were often installed before a donor was found. Nevertheless, these features help establish a reasonable date range.

Composition and Other Stylistic Elements. These elements are more subjective, and call for a fairly broad knowledge of architecture and art history. Do the windows fit the general style of the building? The style of the window may point to a general stylistic period (e.g., Arts & Crafts, Art Nouveau, Prairie School). The imagery or iconography of the windows may also reveal their overall historical context and establish a general time period.