(a) A person may not sell, manufacture for sale, or possess with intent to sell any item of merchandise made in whole or in part of silver or a silver alloy, which has stamped on it, on a tag attached to it, or on a package in which it is contained, the words “sterling silver”, “sterling”, or any colorable imitation of them, unless at least 0.925 of the component parts of the metal which appear or purport to be silver and of which the item is manufactured are pure silver.

(b) A divergence of 0.004 parts from the standard required by subsection (a) of this section is permitted.