56.—(1) Where a person is convicted of an offence under this Act the court may order that any substance or other thing in respect of which the offence was committed and which is owned by or found in the possession or control of that person be forfeited.
(2) In lieu of forfeiture the court may impose, in addition to any fine, a penalty not exceeding such sum as appears to the court to be the value of that which is liable to forfeiture.