The magician stacks the coins and places them into the spectator's hand. He then asks her to place her hands behind her back and put one coin in each hand, remarking that the silver coin is slightly larger than the copper coin, making them easy to tell apart. The magician asks to see the silver coin which the spectator produces. When the spectator opens her other hand, the copper coin has become a quarter.
This trick literally makes people go crazy! Plus you end relatively clean, I carry this around with me every where.
Scotch and Soda has been a favorite of mine for over 40 yrs. of close-up performing. I highly recommend this trick to any magician or magic hobby enthusiast who does not already have this in their pocket. It is a great easy to learn trick and will always leaving them scratching their heads.
C.Cook - The Amazing Clydini
This was recommended to me and its awesome