This page collects URL schemes for directly linking to records in museum collections.
http://numismatics.org/collection/1944.100.24110, where 1944.100.24110 is the accession number.
both link to the same object.
http://www.britishmuseum.org/research/search_the_collection_database/search_object_details.aspx?objectid=117631&partid=1. Not yet sure if "&partid=1" is always necessary.
http://collection.britishmuseum.org/description/object/WCT133702. This is the same object via the BM's SPARQL endpoint.
http://www.fitzmuseum.cam.ac.uk/opac/search/cataloguedetail.html?&priref=65609, where the value of 'priref' is given as "Reference Number:".
http://quod.lib.umich.edu/cgi/i/image/image-idx?id=S-KELSEY-X-0000.00.0782%5D0000_00_0782 . '0000.00.0782' is an accession number.
http://www.getty.edu/art/gettyguide/artObjectDetails?artobj=7758 . It's not clear that the 7758 here is the basis for a stable identity.
http://www.harvardartmuseums.org/collection/detail.dot?id=1977.216.3192, where 1977.216.3192 is the accession number.
Search form at http://www.hermitagemuseum.org/fcgi-bin/db2www/browse.mac/category?selLang=English but no short URLs for individual objects.
http://www.huntsearch.gla.ac.uk/cgi-bin/foxweb/huntsearch/DetailedResults.fwx?collection=all&SearchTerm=D.192, where 'D.192' looks like the accession number (though that isn't explicitly stated anywhere on the page).
http://cartelen.louvre.fr/cartelen/visite?srv=car_not_frame&idNotice=2776&langue=en is a link to an individual object. It does not seem to be a permanent link into the collection database of the institution.
http://www.smb.museum/ikmk/object.php?id=18217568, where '18217568' is the 'Object Number' as given on the page.
http://lkws1.rdg.ac.uk/cgi-bin/ure/uredb.cgi?rec=67.7.3, where '67.7.3' is the accession number.
http://art.thewalters.org/viewwoa.aspx?id=33305. The 'id' is not documented on each page. Addresses of this form are unlikely to be permanent URIs for objects in the collection.
http://ecatalogue.art.yale.edu/detail.htm?objectId=95360, where 95360 is the object id, not the accession number.