What Brian said. New coins "talk" when they rub against each other. Go for older coins -- I use 1964 Kennedys. I also like the old Walking Liberties.
I thought you were into Franklins!
I really had no idea coin magicians were actually more picky with their coins than card magicians are with their cards...
Oh yeah. It's a thing. Unfortunately, I think that the audience could care less about the coins you use (the look of them, at least), so long as they severe maximum potential toward the magician utilizing them, hence the old 'Walking Liberties', 'Franklins', and 'Kennedies' that date 1964 and back (you want coins that have as much silver as possible and are worn down enough for 'silence'. One is the age, and two being that the silver is, I believe , softer than the current mish-mash of what they implement in coins from 1965 up to today outside of collector and commemorative edition coins go).
I like the 2008 coins because
1) the twins birth year
2) the picture on the back of the 'Eagle' coin is two baby Eagles; twins.
Judging by how I make some judgment calls, even after receiving advice and doing my own thing, it doesn't end up well for me. So I'm going to look for some Walking Liberties.
But I will get 1 or two 2008 Eagles as a compromise. I'll get some Walking Liberties. Do not worry
I checked out a coin shop near the house and they have A TON of old Franklins. They want about $10 for one. 'Jinkies!' Is the word I'd use here as I can definitely get older coins cheaper on the EBay.