So if you got some old junk coins sitting around and plenty of time to kill, you can make one of these for yourself or loved ones. http://makeprojects.com/Project/Coin-Ring-Technique/2272/1 If you have the big bucks and want to make one out of a goid coin, I recommend not using the 24k variety.
One of our members makes coin rings. His are of the double-sided variety and he does nice work. However, I can't remember his name.
That would be CT member Judd... here's an interesting thread in which he posted: http://www.cointalk.com/t161051/
I beat down a clad Kennedy 1/2 a few years ago using a stainless steel teaspoon and a old block of aluminum. Did it at work. lol. Seems to me that it took several weeks to get it into the shape ready to be polished for a coin. It really wasn't large enough for a man's ring so I never finished it. You probably need some Morgan sized or similar. I'd say that silver would probably be easier to shape than clad but on the other hand clad will give you a color other than just silver. A clad Ike might be nice.
I noticed this one on ebay the other day. very Kool. http://www.ebay.com/itm/Amazing-Rin...56?pt=Coins_US_Individual&hash=item1e70e4b8ac