To follow up on Craig's recommendation of Acryloid B-72 in acetone (with which
I agree completely).  A reference which gives a reference for making up
Acryloid B-72 in acetone is Koob, Stephen P.  "The Use of Paraloid B-72 as an
Adhesive: It's application for Archaeological ceramics and other materials",
Studies in Conservation 31(1986) 7-1.  (Paraloid is the European marketing
name for Acryloid.)  You can buy it from Conservation Materials.
 
For those of you who remember the whiteout "controversy" - Acryloid B-72 makes
a good, very stable, lacquer to go under and over your number on the object.
Use it at a 10% solution.
 
Jessie Johnson
Assistant Conservator
Texas Memorial Museum
University of Texas at Austin
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