Cleaning minerals

Our mineral exhibit was recently damaged by a flood and we're in the
process of constructing a new one. The curator of geology wishes to
have some of the mineral specimens cleaned before they are
re-displayed. The major problems here are many years of museum dirt
on surfaces, and some tarnish on the metallic specimens. Ultrasonic
cleaning in a tank filled with either water or some solvent like
kerosene has been suggested. Do you have any thoughts on this? I
would appreciate any ideas or comments on alternative treatments.

Katharine Hall

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                  Conservation DistList Instance 9:49
                Distributed: Thursday, December 14, 1995
                        Message Id: cdl-9-49-013
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