If your acceptors are single-coin electronic, you won't find any. I considered programming the IDX acceptors to take them but then I'd have to sift through the quarters to locate them.
When I program the IDX acceptors I have a 1965 and a 1972 that I drop through while programming, otherwise it will reject them. If I ever find time to sort through the quarters for silver ones I might have to program it to take them too.
I have all IDX MA800's and I have NEVER programmed a silver quarter, but I get about 5-10 a month!!! I count all coins through a drop counter and you hear them go thru. Also if you use TD Banks Penny machine it will not accept the silvers, be sure to check the coin chute when you drop coins. I usually go once a year if silver is up and cash them in.
Is there a good way to find these other than sound? We are getting a fair amount of quarters, sorting them by hand and found one already, but thinking there has to be a faster way.