Way back when I went to the Goldsmith's one day tutorial day on hallmarking. Talking to the actual assayers their number one hate was tiny zip lock bags with one item in each. time wasting fiddling. Why antagonise someone working on your stuff? Why make their life harder? Wrap all identical items in one length of bubble with one specimen easily visible and accessible. Chances are only that one will be checked if the materials look the same for all.