GB 11887 is the People's Republic of China's national standard governing the fineness marking, nomenclature, and minimum purity requirements for precious-metal jewellery sold or manufactured within mainland China. Administered by the Standardisation Administration of China (SAC), it is a mandatory — rather than voluntary — standard, meaning compliance is a legal requirement for all jewellery placed on the Chinese domestic market. Its scope encompasses gold, platinum, palladium, and silver articles, and it establishes the system of parts-per-thousand fineness marks — such as Au990, Au750, and Pt950 — that Chinese consumers and trade professionals encounter on hallmarked jewellery. Because China is consistently the world's largest or second-largest gold jewellery market by volume, GB 11887 carries substantial global trade significance: international manufacturers and brands exporting to China must align their marking practices with its provisions.

Background and Legislative Context

China's national standards system uses the prefix GB (from Guójiā Biāozhǔn, meaning "national standard") to designate mandatory or recommended standards issued under the framework of the Standardisation Law of the People's Republic of China. GB 11887 was first issued in 1989 and has undergone several revisions; the edition most widely referenced in contemporary trade is GB 11887-2012, which came into force on 1 September 2013. This revision tightened nomenclature controls, standardised the format of fineness stamps, and clarified the permissible alloy compositions for each precious metal category. The standard is enforced through the General Administration of Market Supervision (formerly the General Administration of Quality Supervision, Inspection and Quarantine) and through local market supervision bureaux, which conduct periodic inspections of retail jewellery.

Precious Metals Covered

GB 11887-2012 addresses four precious-metal categories, each with defined minimum fineness grades expressed in parts per thousand (‰):

• Gold (Au): Recognised fineness grades include 999 (often marked Au999 or colloquially described as "pure gold" or 足金), 990 (Au990), 750 (Au750, corresponding to 18-karat gold), and 585 (Au585, corresponding to 14-karat gold). The standard also accommodates 916 (Au916, 22-karat) in certain product categories. The 999 and 990 grades are particularly significant in the Chinese retail market, where high-fineness yellow gold jewellery — closely related to the Hong Kong tradition of Chuk Kam (足金, 99.0% or above) — commands strong consumer preference.
• Platinum (Pt): Recognised grades are 950 (Pt950), 900 (Pt900), and 850 (Pt850). China is one of the world's largest consumers of platinum jewellery, and the Pt950 designation is the dominant grade in the bridal and fashion segments.
• Palladium (Pd): Recognised at 950 (Pd950) and 500 (Pd500), reflecting palladium's periodic use as a white-metal jewellery alloy, particularly during periods of elevated platinum pricing.
• Silver (Ag): Recognised grades include 999 (Ag999) and 925 (Ag925, sterling silver). The 990 grade (Ag990) is also accommodated.

Marking Requirements

The standard prescribes a specific format for fineness marks. Each article must bear a stamp that combines the chemical symbol of the principal precious metal with the fineness expressed in parts per thousand — for example, Au750 for 18-karat gold or Pt950 for 950-grade platinum. Where a manufacturer's trademark is present, it must appear alongside the fineness mark. The standard explicitly prohibits the use of karat designations (K marks) as the sole identification, though karat designations may appear supplementarily in some contexts; the parts-per-thousand mark is the primary required identifier. This distinguishes Chinese practice from European and North American conventions, where karat or millesimal fineness marks are used more interchangeably.

GB 11887-2012 also prohibits descriptive terms or trade names that could mislead consumers about metal content. For instance, marketing language implying a higher fineness than the article actually possesses — or the use of vague terms such as "gold-coloured" for plated base-metal goods without clear disclosure — is inconsistent with the standard's consumer-protection intent, even if such language falls under separate advertising regulations.

Relationship to Chuk Kam and High-Fineness Gold

The prominence of the Au990 and Au999 grades in GB 11887 reflects a deep cultural preference in Chinese jewellery markets for high-fineness gold. This preference is closely related to the tradition of Chuk Kam (足金), which originated in Hong Kong and Cantonese-speaking communities and denotes gold of at least 99.0% purity. In mainland China, high-fineness gold jewellery — often fashioned as bangles, necklaces, and investment-oriented pieces — is purchased both for adornment and as a store of value. The GB 11887 framework legitimises and standardises this market segment by providing clear fineness definitions and marking requirements that consumers and regulators can rely upon.

International Trade Implications

For international jewellery manufacturers — whether European, North American, or from other Asian producing centres — GB 11887 compliance is a non-negotiable condition of market access in mainland China. A common point of adjustment for exporters is the shift from karat-centric marking to the parts-per-thousand format. An 18-karat gold article marked simply "18K" in its country of origin must be re-marked or additionally marked as Au750 to satisfy Chinese customs and retail requirements. Similarly, platinum articles marked "PLAT" or "PT" followed by a fineness in the Western convention must conform to the Pt + numeric format.

International luxury brands operating boutiques in mainland China — including those with European hallmarking traditions — must ensure that goods sold through Chinese retail channels carry compliant marks, whether applied at the point of manufacture or through authorised re-marking processes. The China National Gold Group and major domestic retailers such as Chow Tai Fook and Lao Feng Xiang operate entirely within the GB 11887 framework and serve as de facto benchmarks for compliance practice.

Consumer Protection and Enforcement

The mandatory character of GB 11887 means that non-compliant jewellery is subject to market withdrawal, fines, and reputational consequences under China's product quality and consumer protection legislation. Local market supervision authorities conduct spot checks at retail level, and laboratory testing of metal fineness — typically by X-ray fluorescence (XRF) analysis or fire assay — is used to verify that stamped fineness values correspond to actual composition. Consumers who purchase jewellery bearing a GB 11887-compliant mark have a legal basis for complaint if the article fails to meet the stated fineness, providing a consumer-protection mechanism that underpins confidence in the formal retail jewellery sector.

Further Reading

• GIA Gems & Gemology — China Jewellery Market Notes
• American Gem Trade Association — International Standards Resources