[Centurion2000]

Your quote would seem to grant a specific exemption for gold and silver coin

True, but they are selling paper money, not coin.

[Oberon]

Hmmm. This could get very ticklish. Technically, this means that if I borrow a silver coin from you and write you a receipt for it, I've broken the law. That's all that real money is, you know... a receipt for real currency (i.e. coin or bullion) on deposit.