Please excuse cross-postings - I am sending this to the conservation list
as well:

We have in our institutional archives a group of photo-etched copper
printing blocks.  The copper plates are mounted on hardwood blocks -
probably cherry, by its look - and have been stored in a corrugated
cardboard box with sheets of newsprint paper between them.  They were done
in the fifties and have probably been stored this way since then.  When
removed from this less-than-optimum storage, they were found to have
numerous spots of green corrosion on them, in some cases merging into a
solid area; there are also areas of what looks like black deposits.  I need
advice on the possibility and / or advisability of removing this corrosion
to prepare the objects for exhibition, and on the best way to store them.
Our archival storage environment is not at this time well controlled or
monitored, so establishment of a microclimate (on a limited budget) would
probably be the way to go.

I will be consulting the CoOL archives as well, but thought some of you
might have direct experience with such blocks.

TIA - Anne
Anne T. Lane
Curatorial Assistant
Museum of York County
4621 Mount Gallant Road
Rock Hill, SC 29715
803-329-2121, ext 104
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