I recently ran across an article about Coin Shrinking and it reminded me of the miniature coins I have in my collection that always seemed to elicit far more interest than most of the other coins. People seem to like anything that’s miniature. You could take a ferocious animal that they’re mortally afraid of, but if you shrink it down to the size of a pea, it becomes cute.
In any case, the shrinking process involves quickly discharging a high energy capacitor bank through a work coil to generate a very powerful and rapidly changing electromagnetic field which then forms the metal to be fabricated. It’s not something to do if you’re inexperienced, but the results are pretty cool. Just make sure you shrink coins that aren’t worth much.