Upon the showing of sufficient interest by gold producers, the department shall contract with a registered, certified mint for the minting of gold medallions in an amount and in such sizes as deemed appropriate. Gold producers shall provide all gold bullion necessary for minting and shall deliver it to the mint for processing. They shall pay in advance to the department a fee sufficient to cover all minting and handling costs; royalty fees for the use of the seal; and reimbursement costs to the department for designing the medallions.