Wis. Stat. § 134.28: Misbranding of base silver articles.

Except as provided in s. 134.29, any person who sells any article of merchandise made in whole or in part of silver or of any alloy of silver marked in way, other than with the word “sterling” or the word “coin”, indicating, or designed or intended to indicate, that the silver or alloy of silver in the article is of a greater degree of fineness than the actual fineness or quality of the silver or alloy, unless the actual fineness of the silver or alloy of silver of which the article is composed is not less by more than four one-thousandths parts than the actual fineness, is guilty of a misdemeanor.