13 GCA § 3107: Money.

(1) An instrument is payable in money if the medium of exchange in which it is payable is money at the time the instrument is made. An instrument payable in currency or current funds is payable in money.

(2) A promise or order to pay a sum stated in a foreign currency is for a sum certain in money and, unless a different medium of payment is specified in the instrument, may be satisfied by payment of that number of dollars which the stated foreign currency will purchase at the buying sight rate for that currency on the day on which the instrument is payable or, if payable on demand, on the day of demand. If such an instrument specifies a foreign currency as the medium of payment the instrument is payable in that currency.