15 U.S.C. § 292

Any gold, silver, or goods manufactured therefrom after February 21, 1905, bearing any of the stamps, words, phrases, or devices prohibited to be used under section 291 of this title, and being in the course of transportation from one State to another, or to or from a Territory, the District of Columbia, or possessions of the United States, shall be forfeited to the United States, and may be seized and condemned by like proceedings as those provided by law for the forfeiture, seizure, and condemnation of property imported into the United States contrary to law.