Slide mounts for treatment documentation

For conservation treatment color slides, I have the option of using
the local film processor, who uses plastic slide mounts (white
plastic; feels polystyrene-like, they are fairly typical from what I
have seen), or sending them away to Kodak for paper mounts.  The
paper mounts make it easier to label the slides, but it is so
convenient to have the slides done locally.

My concern is about the potential long term effects of deteriorating
paper mounts as opposed to deteriorating plastic, which would be a
better choice? Does it make a difference? (I mean, if I could spare
someone in the future the trouble and expense of having to change
slides mounts for thousands of slides, it would be worth knowing if
one choice is better than the other). The slides will be stored in
polyethylene slide sleeves in notebooks with slipcases.  I also have
some older slides that were mounted in metal mounts (some kind of
white metal, done in the 1970's) with glass "windows", should these
be changed? Suggestions?

Ellen Rosenthal
Corning Museum of Glass
Corning NY 14830

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                  Conservation DistList Instance 11:32
                  Distributed: Monday, October 6, 1997
                       Message Id: cdl-11-32-013
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