HIGH-PRECISION MEASUREMENT OF PRECIOUS ME TALS IN JEWELRY ALLOYS USING ICP-OES ISO STANDARD METHODS FOR AN INTERNATIONALLY HARMONIZED MARKET/

The large quantities of precious metals in circulation in jewellery as well as the recent opening of the international markets have increasi ngly made jewellery a subject matter of standardization. As usual in c onjunction with standards, the description of the properties of jewell ery and the methods for their verification stand in the foreground in this context. The Technical Committee ''TC 174 Jewellery'' of the ISO and the committee ''TC 283 Precious Metals Applications in Jewellery a nd Associated Products'' of the CEN are in charge of this standardizat ion of jewellery on an international level. The ''Working Group 1'' de velops for the two committees the analytical methods which are suitabl e for incorporation in the standards for the determination of the mill esimal fineness of jewellery alloys. An important issue of this workin g programme is the clarification of the question of how precise the pr ecious metal contents in the jewellery alloys of the ISO 9202:1991 (E) standard can be determined using the standard methods specified by th e analytical working group. The answer to this question will greatly c ontribute towards the harmonization of the international jewellery mar kets.