Green corrosion on brass

I am working on a leather object covered with detailed beadwork. My
request concerns the brass beads which are corroded by fatty acids
from an applied leather dressing. The brass beads are now completely
covered with green corrosion products (identified as copper and zinc
soaps). The brass beads are threaded on sinew and these strands are
in turn stitched to the leather by cotton thread. Has anybody dealt
with a similar situation? I would be glad to learn about your
experiences. I am trying to clean the brass without harming the
organic materials.

Ute Werner
Canadian Conservation Institute


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                  Conservation DistList Instance 23:18
                 Distributed: Friday, November 20, 2009
                       Message Id: cdl-23-18-013
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