ISO 22764:2020 Jewellery and precious metals — Fineness of solders used with precious metal jewellery alloys.
platinum, gold, palladium and silver in the pure state and their alloys
precious metal alloy
solid mixture of a precious metal (12) with one or more other metals made by melting or an electrochemical technique
alloy used to join metal parts
4 Requirements with regard to fineness
4.1 Mean fineness
The solders shall not decrease the measured mean fineness below the declared fineness.
4.2 Gold jewellery
For joining parts of gold jewellery solder shall be used with at least the same fineness as the article which will be soldered.
Exceptions to the above are:
— Red and dark red gold alloy articles (as described in ISO 8654) with a fineness equal or more than 750 %o shall be soldered with a solder of a minimum fineness of 585 %o gold.
— Other gold alloy articles with a fineness of more than 750 %o shall he soldered with a solder of a minimum fineness of 750 %o gold.
— Gold chains made from the wire with less than 1 mm diameter can be soldered with any solder, including goldiess ones.
4.3 Platinum jewellery
For joining parts of platinum jewellery solder shall be used with a minimum total content of precious metals of 800 O&
4.4 Palladium jewellery
For joining parts of palladium jewellery solder shall be used with a minimum total content of precious metals of 700 %o.
4.5 Silver jewellery
For joining parts of silver jewellery solder shall be used with a minimum fineness of 550 % silver.
5 Determination of fineness
For the determination of the fineness the methods given in the specific reference standards ISO 11210, ISO 11426, ISO 11427, ISO 11490, ISO 11494, ISO 11495, ISO 13756, ISO 15093 and ISO 15096 shall be used.ISO 22764 pdf download.