Interesting - so you exchange currency for one of these cards, which at the time of purchase has approximately the same amount of silver that any exchange would take for the equal amount of currency spent.  It is value based on the precious mineral and not any currency.  Same as purchasing a bitcoin.

However, I guess more merchants would be willing to accept a slice of silver over a bitcoin, simply because it is easier for the merchant to understand and figure out how much that silver is worth.  However, it cannot be widely accepted as currency, since most merchants will not carry a scale capable of verifying the card's claim of 1/10 of a gram.

Thanks error, I did not know such a service existed!