Having worked in a museum and aided several others, plus having a couple of degrees in history, my personal policy on display material is very simple: I DONATE NOTHING, but I will LOAN ALMOST ANYTHING.
This way the material is shown to the public but remains your property. You can leave it to your kids or whatever, but educate them along the same lines as to having some regard for our history; they just might surprise your ghost and keep the loan in operation.
Do it this way and you can be pretty sure that the items won't be just shovelled into a box, allowed to get wet.... and then thrown out.
Yes, museums DO throw things out. I have a collection of WWI manuals, about half of which are directly traceable to a single individual. I hauled them out of a museum's garbage bin before the sanitation department got there.
LOAN, not give..... if you respect the things yourself.
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