Coins

I'm afraid I'm rather in over my head here, and am hoping someone
from the list can help me tread water:  We have a biblical coins
collection housed in our library that includes samples of many of
the currencies referenced in both the Old and New Testaments. The
coins range in date from 600 BC to 2nd century AD.  One of our
faculty members (who was largely responsible for acquiring the
collection) has been concerned about deterioration of the coins in
the collection and is urging the library to get the coins restored
and properly preserved.

Each coin is mounted inside of a 4 x 2 x 1/2 inc block of what
appears to me to be solid acrylic.  If I look at one of the blocks
edgewise, I can see a thin line running through the middle that
makes it look like each coin was laid flat on a thin block of
acrylic along with a translucent label identifying the coin, and
then a layer of acrylic was poured on top, sealing in the coin and
its label.  The gold and silver coins appear to my untrained eye to
still be in good condition, but the bronze coins show a lot of
corrosion.  (One coin, identified as a lepton from 37-44 AD, has
discolored the acrylic around it with a purple haze.)

I have volunteered to do the initial legwork in figuring out what it
would take to restore the collection.  Specifically, I am wondering
if it is even possible to undo the damage that has been done--can
the coins be extracted from the acrylic without being destroyed? And
who would do this kind of work?  Since we're located very close to
Chicago, I'm guessing that there might be somebody relatively close
by who would know what to do with these coins. What it would
actually cost is a question that can wait until later once we know
what is possible. Any suggestions or references will be gratefully
accepted,

Blake Walter, Head of Technical Services
Rolfing Library
Trinity International University
2065 Half Day Rd, Deerfield, IL 60015
847-317-4006
Fax: 847-317-4012


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                  Conservation DistList Instance 14:51
                  Distributed: Tuesday, April 3, 2001
                       Message Id: cdl-14-51-020
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