Business and Professions Code § 22130

22130.

In any action relating to the enforcement of any provision of this article, a certificate duly issued by an assay office of the Treasury Department of the United States, certifying the weight of any article, or any part thereof, or of the kind, weight, quality, fineness or quantity of any ingredient thereof, shall be receivable in evidence as constituting prima facie proof of the matter or matters so certified.