Yellowing polyethylene bags containing Pacific Silvercloth

We have recently had multiple-instances of yellowing of polyethylene
bags containing silver objects wrapped in Pacific Silvercloth.  The
objects had been first wrapped in acid-free tissue and then in the
Silvercloth prior to placing them in the poly bags.  Each instance
occurred after the objects were packed in this way and crated for
shipment for outward loan.  No tarnish or other issues were seen on
the silver objects. Has anyone experienced this before?

Jakki Godfrey
Associate Objects Conservator
Brooklyn Museum


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                  Conservation DistList Instance 28:8
                   Distributed: Friday, July 25, 2014
                        Message Id: cdl-28-8-010
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