This International Standard specifies a docimastic method (cupellation method) for the determination of gold in gold jewelry alloys. The gold content of the alloy should preferably be between 333 and 999 per mille (). The process is particularly applicable for gold alloys with silver, copper and zinc. Some changes to the process are indicated if nickel and/or palladium are present in so-called white gold alloys, as well as for alloys containing more than 990 per thousand () gold. This method is specified as the recommended method for determining purity in alloys as provided for in ISO 9202.
EN ISO 11426:2016 Referenced Document
ISO 11596:2008 Jewellery - Sampling of precious metal alloys for and in jewellery and associated products
ISO 9202:2014 Jewellery - Fineness of precious metal alloys
EN ISO 11426:2016 history
2021EN ISO 11426:2021 Jewellery and precious metals - Determination of gold - Cupellation method (fire assay) (ISO 11426:2021)
2016EN ISO 11426:2016 Jewellery - Determination of gold in gold jewellery alloys - Cupellation method (fire assay) (ISO 11426:2014)
1998EN ISO 11426:1998 Determination of gold in gold jewellery alloys - Cupellation method (fire assay) (ISO 11426:1997)