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Conservation

Brass Urn with Shell and Fruit Design

photo of the brass urn, before treatment
Before Treatment

photo of the brass urn, after treatment
After Treatment

This brass urn can clearly be seen in the oldest photographs of the Ramsey house interior that we have, showing how the house looked shortly after construction was complete. The urns were purely decorative, and never contained ashes or anything else. In fact, normally a central internal bolt tightly holds them together. The brass had been regularly cleaned and polished by the housekeeping staff for over a century. Using commercial metal polishes over this period of time will cause significant abrasion and loss of detail. Additionally, unless a metal object is disassembled when it is polished, it is nearly impossible to completely remove the metal polish residue from all of the crevices, and when left there, this residue can start highly corrosive electrochemical cells that badly corrode the metal.

The urns were completely disassembled. The iron parts were cleaned with a fine wire brush, the rust was passivated with a tannic acid solution, and then the iron was coated with wax for protection. The brass parts were cleaned with disodium EDTA, a chelating agent, which removed most of the tarnish and corrosion. After this it was washed with a mild surfactant, rinsed in water, and dried with a soft cloth. It was then degreased with acetone, and completely dried in a laboratory oven at 50 degrees Celsius. Finally, the threads were protected with wax film, and the brass was spray-coated with Acryloid B-48N. After drying, the wax film was removed from the threads, paste wax was applied to them, and the urn was reassembled.