Cal. Rev. & Tax. Code § 6354

There are exempted from the taxes imposed by this part, the gross receipts from the sales of commemorative “California Gold” medallions produced and sold in accordance with Chapter 25 (commencing with Section 7551) of Division 7 of Title 1 of the Government Code, and the storage, use, or other consumption in this state of commemorative “California Gold” medallions so produced and sold.