Note to Paragraph (c)(1): Use of the term "Gold" or any abbreviation to describe all or part of a product that is composed throughout of gold alloy, but contains a hollow center or interior, may mislead consumers, unless the fact that the product contains a hollow center is disclosed in immediate proximity to the term "Gold" or its abbreviation (for example, "14 Karat Gold-Hollow Center," or "14 K. Gold Tubing," when of a gold alloy tubing of such karat fineness). Such products should not be marked or described as "solid" or as being solidly of gold or of a gold alloy. For example, when the composition of such a product is 14 karat gold alloy, it should not be described or marked as either "14 Kt. Solid Gold" or as "Solid 14 Kt. Gold."
Note to Paragraph (d): Exemptions recognized in the assay of karat gold industry products and in the assay of gold filled, gold overlay, and rolled gold plate industry products, and not to be considered in any assay for quality, are listed in the appendix.
16 C.F.R. §23.3