I have acquired 2kg of assorted coins from various countries. These are to spice up board games by using real metal coins, using material to indicate denomination rather than numbers on the coin eg copper = 1 groat, silver = 5 groats, gold = 10 groats.
I know the advice for valuable coins is never to clean them but these don't have any collectable value. Almost all of them are very dirty and I'd like to get them to a condition where they are pleasant to handle, not necessarily gleaming (but that would be nice). I'm prepared to separate the copper, silver and gold coloured coins (being from different countries, the exact alloy will vary), but I don't want to have to scrub them individually.
I'm also somewhat wary of using acids as this cleans very effectively but leaves the metal dull at least with copper.