AIC's 53rd Annual Meeting

In preparation for the Colonial Williamsburg Foundation’s new Colin G. and Nancy N. Campbell Archaeology Center (CAC) scheduled opening in 2026, conservation was undertaken on a variety of objects selected for display in the new exhibition spaces. As the fellows hired to begin this process, part of our work was the treatment of two carboy bottles. The glass bottles, one clear and one green, were first assembled in the 1980s following excavation from the historic site of the Public Hospital. By the 2020s, the bottles’ original use is unclear, the old adhesives were visibly degrading, and no treatment records could be located. Additionally, after decades in open storage in the Archaeology Collections Building, the soon-to-be predecessor of the CAC, the bottles were obscured by surface dust. Over eight months, we examined, documented, disassembled, cleaned, and reassembled the two bottles, becoming familiar with a variety of adhesive reversal methodologies in the process.

There are 138 clear and 187 green fragments, creating the project’s first challenge. The sheer number of fragments required a mapping system to denote their locations on the bottles. We created a panorama map for each bottle, on which every fragment received a unique name and a physical label to identify it throughout treatment. We also devised a spreadsheet to track the treatment progress of each fragment. At about two feet tall, these bottles required close teamwork, clear communication, and comprehensive organization.

Another challenge of this project was the unknown adhesives from previous mending. These generously applied, yellowed adhesives were not only visually distracting but also posed risks to the bottles’ structural stability. FTIR analyses revealed Duco rubber cement and Epotek 301 on the clear bottle, and epoxies – most likely Fynebond and Epotek 301 – on the green bottle.

We undertook treatment on the clear bottle first, and one of its adhesives proved extremely tenacious. To find an effective treatment method for what was likely epoxy, reversal testing was performed to find ZipStrip (methylene chloride) alternatives. First, hot water and 1:1 acetone and ethanol baths were tried, but both were unsuccessful. Next, four solvent bath combinations were tested with 49 xylenes:45 acetone:6 ethanol proving to be the most effective, which reversed many joins and minimized the use of ZipStrip.

Surprisingly, the green bottle proved much easier to disassemble despite the FTIR results conclusively showing epoxies. Most joins were successfully reversed with 1:1 acetone and ethanol vapor chambers and baths. The few tenacious joins were reversed with 49 xylenes:45 acetone:6 ethanol baths. Testing from the clear bottle treatment provided an effective solvent combination to tackle the stubborn joins, significantly saving time during the second treatment.

The scale and complexity of the project required creativity, collaboration, and eventually tacit understanding between the two of us. Organization was key, with the panorama map and spreadsheet preventing disassociation and ensuring smooth coordination. Reversal testing revealed safer methods for removing epoxies. After much time and dedication, the two bottles are revitalized and ready for display in the new CAC building.