Okay that one is new to me, but it's addressing a fairly specific problem. I was referring to
http://www.law.cornell.edu/uscode/text/18/331, which is older and more general. I know of many pawn/coin/collector shops which actively buy silver quarters/dollars and copper pennies for the purpose of melting them for the metal.
Yeah. The Treasury/Mint issued new regulations to prevent melting pennies and nickels when commodity prices spiked. The US Code you refer to deals with counterfeit mainly.
common practice for jewelers. If you can find a reputable legit jeweler, and have foreign coin to sell - they'll usually pay a little more for it because it's not illegal to melt them.
Some foreign coins are not covered by the treasury/mint regulations.