Pacific Silver Cloth

In response to Larry Hutchings' inquiry about storing objects in
Pacific Silver Cloth and then bagging in polyethylene, I would
suggest that this is an effective way to multiply the effect of the
silver cloth.  If the pollutants are excluded, the exposure of the
object and the silver cloth will be greatly reduced, and the
duration of the protection will be greatly increased.  Sealing in
mylar would increase the duration of protection dramatically and
might make the silver cloth unnecessary, but mylar is expensive and
difficult to seal securely.  Access to the objects also becomes a
consideration with mylar, due to the cost of replacement and/or the
difficulty of re-sealing after opening.

VCI (vapor phase corrosion inhibitor) materials are also available
and are sometimes useful for display cases or storage cabinets.
Small sized cartridges (small sections of plastic tube enclosing a
piece of treated foam) can also be used in plastic bags. Typically,
a properly sized cartridge in a reasonably enclosed space will last
about two years.  A variety of VCI products are available, but only
a few are safe for silver or mixed metals.

Geoffrey I. Brown
Curator of Conservation
Kelsey Museum

                                  ***
                  Conservation DistList Instance 10:56
                Distributed: Tuesday, December 10, 1996
                       Message Id: cdl-10-56-004
                                  ***