"above, was a reference the sound made when the dealer plucked a $2.50 chip from a rack of chip as part of the pay-off for a natural 21 in a blackjack game."

See if you can make a $2.50 chip "SNAP" when you pluck it from the rack.
If you can make it "SNAP" 3 times in a row, then I will concede you can refer to it as a snapper!!!!!!!!!!

If not??? It is just a $2.50 chip!!!!