I think they should make coins out of foil wrapped chocolate. You pay cash and get change that's edible. No need to have change jars cluttering ones home. Coins getting sent to the TPGs will need to be refrigerated. Collections can be kept in the freezer. No, I haven't been drinking, yet.
The committee that has been studing materials for the past ten years trying to find a replacement material for the cent and five cent have repeatedly considered a stainless steel composition. And they keep coming to the conclusion that the material is too hard and doesn't strike up sufficiently. (Then after making their biannual report they go back and test it again. It didn't work last time, maybe it will work this time.) They also have the problem that some of the tested alloys are magnetic which would require changing all the coin mechanisms which make them a hard NO, because they want a material that can be seamlessly be introduced along with the existing coins that won't require major adjustments to existing infrastructure. Considering SS coins of the same size would be almost 20% lighter that pretty much makes them a non-starter.
One day I hit a penny with metal polish a few too many times, and it wore off 10% of the copper showing the zinc below. Looked like crap.