The way you describe it, three numbers for each object seems inescapable, even
if a bit much.  Here are my thoughts:

Your LOAN Number:  This should be assigned when the objects arrive at your
museum and never change.  You might anticipate or "pre-assign" them ahead of
time, but making changes based on what actually arrives vs assigning all the
numbers at arrival... you'll have to decide which takes more time or causes
more bottlenecks.  In any case, this is the number that I would suggest be
used as the primary access to the object record in your computer database.
And also by the rest of the staff of the museum.  Our loan numbers start with
TL. then have lot item and year, eg: 'TL.5.12.1995'. We put the year at the
end so that if someone drops the TL the number still does not look like an
accession number.  If you wanted to number the exhibits, the lenders and the
items you might make numbers that looked like: 'TL.7.5.12.1995'.  Thus all obj
ects whos loan numbers started with TL.7 would be for the same show.  This
seems most logical.

Lending Museums ACCESSION Numbers:  This is their number.  You may need to
record, even publish it.  But it's just text, and I wouldn't bother any more
about it than about any other assigned attribute of the object, like title or
medium.

Catalogue numbers:  Try to let the catalogue designers and museum educators
worry about this.  Don't use their proofs or printouts for any registration
functions, use your own lists, and try to encourage them to do the same.  Of
course these are going to change as the exhibit design and layout evolves, but
do you really need to record these?  Maybe enter them only after the show has
crystallized.

'nuff said.

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   Stephen B. Ringle, Registrar             [log in to unmask]
   University of Maine Museum of Art
   5712 Carnegie Hall, Room 109              vox: 207-581-3257
   Orono, Maine   04469-5712                 fax: 207-581-3083
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