MOTM

Easier to use a piece of steel wool on the board. This is standard procedure for bare copper PCBs which oxidize very quickly when left exposed to the elements.

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> What I would suggest (ROHS or not) would be to take an old (ie, not used for anything other than electronics) sponge (or rag) and some powdered cleanser (eg: Ajax) and water, and give the boards a little scrub to brighten up the copper and remove any tarnish/oxidization.
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