The FTC Guides for the Jewelry, Precious Metals, and Pewter Industries — codified at 16 CFR Part 23 and administered by the United States Federal Trade Commission — constitute the primary regulatory framework governing how gemstones, precious metals, and jewellery products may be described, advertised, and sold within the American market. First issued in 1957 and substantially revised most recently in 2018, the Guides establish enforceable standards for terminology, mandatory treatment disclosure, synthetic and simulant identification, and metal-purity marking. Although technically administrative guidance rather than statute, the Guides carry the practical force of law: conduct that departs from them is presumed to be an unfair or deceptive act under Section 5 of the FTC Act, exposing violators to civil penalties, injunctions, and mandatory corrective advertising. Any retailer, wholesaler, importer, or laboratory operating in the United States market — and, by extension, any international supplier whose goods enter that market — must be conversant with their requirements.

Legislative and Regulatory Foundation

The Guides derive their authority from two overlapping sources. The first is the Federal Trade Commission Act of 1914, which prohibits unfair or deceptive acts or practices in commerce. The second, for metal-purity claims specifically, is the National Stamping Act (15 U.S.C. §§ 294–300), which regulates the marking of gold, silver, and platinum articles sold in the United States. The FTC Guides translate both bodies of law into practical, industry-specific guidance, defining precisely which words, abbreviations, and numerical designations are permissible and under what conditions. The 2018 revision — the most significant update in several decades — responded to technological changes in the gem trade, particularly the commercial emergence of laboratory-grown diamonds and advances in gemstone treatment.

Gemstone Terminology and Misrepresentation

A central concern of the Guides is the accurate naming of gemstone materials. The Guides prohibit using the unqualified name of a natural gemstone species to describe a material that is not, in fact, that natural species. Consequently, a laboratory-grown ruby must not be advertised simply as a "ruby" without a qualifying disclosure; terms such as laboratory-grown, laboratory-created, synthetic, or [manufacturer's name]-created are all acceptable qualifiers, provided they appear with equal prominence to the gem name itself.

The 2018 revision generated considerable industry debate by removing the word synthetic from the list of required or preferred qualifiers for laboratory-grown diamonds specifically, on the grounds that "synthetic" implies inferior quality and may mislead consumers in the opposite direction — suggesting the material is not genuine diamond. The Commission concluded that "laboratory-grown," "laboratory-created," or "man-made" are clearer to consumers. This change was contested by segments of the natural-diamond trade but reflects the FTC's consumer-protection mandate rather than any mineralogical judgement.

Simulants — materials that resemble a gemstone without sharing its composition or structure — must be identified as such. Describing cubic zirconia, for instance, as a "diamond" without qualification is explicitly prohibited. Trade names that obscure the true nature of a simulant (such as historically common names like "Herkimer diamond" for quartz) are permissible only when accompanied by clear disclosure of the material's actual identity.

Treatment Disclosure Requirements

The Guides require disclosure of any treatment that is not permanent, that requires special care, or that has a significant effect on the gem's value. This obligation applies at every level of the supply chain — from importer to wholesaler to retailer — and extends to advertising as well as point-of-sale communication.

Specific treatments addressed include:

• Fracture filling and clarity enhancement in diamonds and coloured stones, which must be disclosed because the treatment is not permanent and affects value.
• Heat treatment of coloured gemstones. The Guides acknowledge that some treatments — such as the routine heating of sapphire and ruby — are so pervasive and widely known within the trade that disclosure, while still recommended, may not always be legally mandated in every context. However, the safer and more widely adopted industry practice is full disclosure regardless.
• Irradiation of coloured stones and pearls, which must be disclosed.
• Coating, dyeing, and impregnation of gemstones, all of which require disclosure.
• Beryllium diffusion and other lattice-diffusion treatments of corundum, which alter colour and must be disclosed.

The Guides do not mandate a specific disclosure format, but the FTC has made clear that disclosures must be prominent, unambiguous, and not buried in fine print. Gemmological laboratory reports — from institutions such as the GIA, AGL, Gübelin, or SSEF — are widely used in the trade as a practical mechanism for satisfying disclosure obligations, though possession of a laboratory report does not automatically constitute legal compliance if the information is not communicated to the buyer.

Precious Metal Standards and the National Stamping Act

The Guides devote substantial attention to the marking of gold, silver, platinum, and pewter articles, operating in conjunction with the National Stamping Act. Key provisions include:

• Gold: Articles may be described as "gold" only if they are composed throughout of an alloy of not less than 10 karats fineness. Karat marks (10K, 14K, 18K, etc.) must be accompanied by the manufacturer's or importer's registered trademark when stamped on an article. Gold-filled, gold-plated, and vermeil articles must be described using those qualified terms, with the karat fineness of the gold layer disclosed.
• Silver: "Sterling silver" denotes an alloy of at least 92.5% pure silver. "Coin silver" denotes at least 90% pure silver. The unqualified term "silver" may be used for articles of at least 92.5% purity.
• Platinum: Articles may be marked "Platinum" without qualification only if they contain at least 950 parts per thousand of platinum. Articles containing 850–950 parts per thousand must disclose the actual platinum content (e.g., "850Pt"). Platinum-group metals used as alloying agents must also be identified.
• Pewter: Must contain at least 90% tin.

Misrepresentation of metal purity — for example, marking a 14-karat article as 18-karat — constitutes a violation of both the Guides and the National Stamping Act and may attract criminal as well as civil liability.

Pearl Terminology

The Guides address pearl nomenclature with similar rigour. The unqualified word "pearl" is reserved for naturally occurring pearls formed without human intervention. Cultured pearls — in which a nucleus has been implanted by human hand — must be described as "cultured" or "cultivated." Imitation pearls, composed of glass, plastic, or other materials, must be identified as such. The Guides also address the use of geographic or variety qualifiers (such as "South Sea" or "Tahitian"), requiring that such terms be used accurately and not applied to pearls of different origin.

Enforcement and Industry Implications

The FTC enforces the Guides through investigation, consent orders, and, where necessary, litigation. Civil penalties for violations of FTC Act Section 5 can be substantial, and the Commission has the authority to require corrective advertising — public statements that correct prior misleading claims — at the violator's expense. The FTC also coordinates with state attorneys general and, in cases involving import fraud, with US Customs and Border Protection.

For the international gem trade, the Guides function as a de facto standard for any supplier wishing to access the US market. Major auction houses, retail chains, and online platforms operating in the United States have incorporated FTC compliance into their vendor agreements and listing policies. The 2018 revision's treatment of laboratory-grown diamonds, in particular, prompted significant policy updates across the industry, including revised grading report language at several major gemmological laboratories.

Industry bodies including the Jewelers Vigilance Committee (JVC) and the American Gem Trade Association (AGTA) publish compliance guidance and training resources to help members navigate the Guides' requirements. The AGTA's own treatment disclosure code is explicitly designed to meet or exceed FTC standards.

Limitations and Scope

It is important to note that the FTC Guides apply to commercial conduct in the United States; they have no direct jurisdiction over transactions conducted entirely outside the US market. They also do not establish gemmological definitions — the FTC is a consumer-protection body, not a scientific authority — and their terminology choices occasionally diverge from those preferred by gemmological institutions. The removal of "synthetic" as a preferred descriptor for laboratory-grown diamonds, for example, conflicts with the longstanding gemmological usage of that term as a neutral, scientifically precise descriptor. Practitioners operating across both regulatory and scientific contexts must be attentive to this distinction.

Further Reading

• FTC Jewelry Guides — Full Text (ftc.gov)
• AGTA Treatment Disclosure Policy (agta.org)
• GIA Commentary on the 2018 FTC Guides Update (gia.edu)