[quote=RAN][quote=Oldelkhunter] I put KG12 on a tarnished penny and it dissolved half of it in no time at all.
Must have been an old penny. The US mint stopped making solid copper pennies in 1982.
RAN
Don't know what year it is , the KG12 dissolved it and best of all it doesn't stink or destroy bores if left in them.
