Hi Lisa,
We consider items like that part of our internal archives rather than our proper collection, so they are catalogued and findable in Past Perfect if, say, a curator wanted to use them in an exhibit, but don't have to go before our collections committee. We have our main collection/archives, which are accessions approved by the board and have all the usual museum collections rules and standards around them, and then we two secondary collections, our internal archives and teaching collection, which staff can add to without board approval and have somewhat laxer rules (eg. the teaching collection items can be touched, staff can also decide to remove things that have outlived their usefulness, etc.). Both are designated in Past Perfect with a prefix on their ID# (IA for Internal Archives and K for teaching). Many of these items are findable in our collections search online, so they can still be useful to researchers and curators, or for a case like yours, the family would still be able to pull up their loved one's plaque even if it's no longer on display.
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Katie Andril
Collections Coordinator
Jewish Museum of Maryland
Baltimore MD
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