ISO Technical Committee 174 (Jewellery) is the body within the International Organization for Standardization responsible for the development and maintenance of international standards relating to jewellery, precious metals, and gemstones. The committee comprises representatives from national standards bodies of participating member countries and develops standards through consensus procedures, with periodic revision to reflect advances in analytical methods, changes in trade practice, and new categories of materials and treatments.

Scope of work

ISO TC 174's published portfolio includes standards on precious-metal fineness designations (ISO 9202), assay methods for gold (ISO 11426 and ISO 15093), silver (ISO 11427), platinum (ISO 11210), and palladium (ISO 11489 and related), the gold-alloy colour designation system (ISO 8654), ring sizes (ISO 8653), diamond grading and disclosure (ISO 24016), and consumer-confidence terminology for the diamond industry (ISO 18323). The committee also addresses pearl terminology, gemstone disclosure, and various ancillary trade standards.

The committee operates through working groups specialising in particular subject areas. Each working group is convened by a national standards body and includes technical experts from member countries, who develop draft standards through iterative review and ballot. Committee draft, draft international standard, and final draft international standard stages each involve member-country review and voting before a standard is published as an International Standard.

Membership

Participating member countries (P-members), with full voting rights, include the major jewellery-trading economies: the United Kingdom (BSI), Germany (DIN), France (AFNOR), Italy (UNI), Spain (UNE), Switzerland (SNV), the United States (ANSI), Canada (SCC), Japan (JISC), India (BIS), China (SAC), South Korea (KATS), Australia (SA), Belgium (NBN), the Netherlands (NEN), and others. Observer member countries (O-members) participate without voting rights. The committee secretariat is held on rotation among major national standards bodies.

Liaison relationships connect ISO TC 174 with related international bodies including CIBJO (the World Jewellery Confederation), the International Gemmological Conference, and the World Diamond Council. CIBJO's Blue Books, while not ISO standards, are developed in close coordination with ISO TC 174 standards and serve as the principal trade-disclosure framework that incorporates ISO standards by reference.

Current activity

The committee's recent priorities have included the development of ISO 24016 on diamond grading and disclosure, the extension of disclosure standards to laboratory-grown diamonds and treated stones, the harmonisation of pearl terminology, the updating of assay-method standards to reflect advances in inductively coupled plasma analysis (ICP-OES, ICP-MS) and X-ray fluorescence techniques, and the response to the rise of laboratory-grown coloured gemstones in commercial quantities. Working groups also address the description and classification of recycled and ethically sourced metals, in coordination with the Responsible Jewellery Council and other supply-chain bodies.

Trade significance

For the working trade, the practical significance of ISO TC 174 is that the standards it produces constitute the international technical framework on which national hallmarking, retail disclosure, and international laboratory practice are built. Buyers of jewellery and gems benefit from a single international standards system rather than a patchwork of conflicting national approaches, and trade contracts frequently reference ISO TC 174 standards directly. The standards are available through ISO at iso.org and through the participating national standards bodies in each country.