ISO Assaying and Analytical Methods for Precious Metals

Transcription

1 ISO Assaying and Analytical Methods for Precious Metals Thomas Brodmann Central Office for Precious Metals Control 3003 Berne, Switzerland ISO ISO stands for International Organization for Standardization, the world s largest developer of voluntary International Standards. ISO is a network of national standard bodies. These national standard bodies make up the ISO membership and they represent ISO in their country. 111 member bodies 49 correspondent members (observers) 4 subscriber members 2 Session 4 - Brodmann 1

2 International Standard What is a standard? A standard is a document that provides requirements, specifications, guidelines or characteristics that can be used consistently to ensure that materials, products, processes and services are fit for their purpose. An International Standard embodies the essential principles of global openness and transparency, consensus and technical coherence. ISO standards are developed by groups of experts, within technical committees (TCs). TCs are made up of representatives of industry, NGOs, governments and other stakeholders, who are put forward by ISO s members. 3 ISO and Precious Metals Analysis ISO TC 174 Jewellery / WG1 Methods for determining fineness (currently at DIN, Pforzheim, Germany) Scope Analytes Jewellery or jewellery alloys; finished or semifinished articles,,, 183 Copper, lead, zinc and nickel ores and concentrates (currently at Standards stralia, Sydney) Copper, lead, zinc and nickel ores and concentrates and are highly appreciated secondary products inter alia,, 4 Session 4 - Brodmann 2

3 Standards issued by ISO/TC 183 (only standards focussing on and/or ) ISO 103:2005 ISO 12740:1998 Copper, lead and zinc sulfide concentrates -- Determination of gold and silver -- Fire assay gravimetric and flame atomic absorption spectrometric method Lead sulfide concentrates -- Determination of silver and gold contents -- Fire assay and flame atomic absorption spectrometric method using scorification or cupellation ISO 152:1999 Zinc sulfide concentrates -- Determination of silver content - - Acid dissolution and flame atomic absorption spectrometric method ISO 15248:1998 Zinc sulfide concentrates -- Determination of silver and gold contents -- Fire assay and flame atomic absorption spectrometric method using scorification or cupellation ISO 15249:1998 Zinc sulfide concentrates -- Determination of gold content -- Acid dissolution/solvent extraction/flame atomic absorption spectrometric method 5 ISO/TC 174 Jewellery WG1 Methods for determining fineness Characteristics Commencement: Stakeholders: Participating Countries: (23) Liaison: 1980ies Refineries, Assay Offices, Mint Offices stria, Belgium, Bulgaria, China, Czech Republic, France, Germany, Hungary, India, Iran Islamic Republic, Ireland, Israel, Italy, Japan, Republic of Korea, Netherlands, Norway, Peru, Russian Federation, South Africa, Spain, United Kingdom, Switzerland CEN TC 283/WG 1 (mandated for providing standards to implement the drafted EU Council Directive on precious metal articles) Note: CEN TC 283 was abolished in Session 4 - Brodmann 3

4 Standards published by TC 174 / WG1 ISO 9202 Fineness of precious metals alloys,, and 10 International standards on determination of fineness in jewellery alloys ISO Sampling of precious metal alloys for and in jewellery and associated products 7 Fineness of precious metals alloys defined in ISO 9202: [417] [958] [990] [990] [990] [990] [999] [999] [999] [999] New fineness in brackets; foreseen in the draft international standard ISO/DIS 9202, (status 2013), not published yet 8 Session 4 - Brodmann 4

5 Standards issued by TC 174/ WG1 (1) ISO 11426:1997 Determination of gold in gold jewellery alloys -- Cupellation method (fire assay) ISO 15093:2008 Jewellery -- Determination of precious metals in 999 gold, platinum and palladium jewellery alloys -- Difference method using inductively coupled plasma optical emission spectroscopy (ICP-OES) 9 Standards issued by TC 174/ WG1 (2) ISO 11427:1993 Determination of silver in silver jewellery alloys -- Volumetric (potentiometric) method using potassium bromide ISO 13756:1997 Determination of silver in silver jewellery alloys -- Volumetric (potentiometric) method using sodium chloride or potassium chloride ISO ISO 15096:2008 Jewellery -- Determination of silver in 999 silver jewellery alloys -- Difference method using inductively coupled plasma optical emission spectroscopy (ICP-OES). 10 Session 4 - Brodmann 5

6 Standards issued by TC 174/ WG1 (3) ISO 11210:1995 Determination of platinum in platinum jewellery alloys -- Gravimetric method after precipitation of ammonium hexachloroplatinate ISO 11489:1995 Determination of platinum in platinum jewellery alloys -- Gravimetric determination by reduction with mercury (I) chloride ISO 11494:2008 Jewellery -- Determination of platinum in platinum jewellery alloys -- Inductively coupled plasma (ICP) solution-spectrometric method using yttrium as internal standard element ISO 15093:2008 Jewellery -- Determination of precious metals in 999 gold, platinum and palladium jewellery alloys -- Difference method using inductively coupled plasma optical emission spectroscopy (ICP-OES) 11 Standards issued by TC 174/ WG1 (4) ISO 11490:1995 Determination of palladium in palladium jewellery alloys -- Gravimetric determination with dimethylglyoxime ISO 11495:2008 Jewellery -- Determination of palladium in palladium jewellery alloys -- Inductively coupled plasma (ICP) solution-spectrometric method using yttrium as internal standard element ISO 15093:2008 Jewellery -- Determination of precious metals in 999 gold, platinum and palladium jewellery alloys -- Difference method using inductively coupled plasma optical emission spectroscopy (ICP-OES) 12 Session 4 - Brodmann 6

7 Scopes of ISO Standards issued by ISO/TC 174 Standard ISO * ISO * ISO * ISO * ISO * ISO * ISO * ISO * ISO ISO *preferably in a range of fineness as stated in ISO 9202, with a palette of typical accompanying elements 13 Analytical methods described in ISO Standards issued by TC 174 Year* Analytical method 1993 Fire Assay, gravimetric Gravimetric Volumetric ICP-OES, direct 2008 ICP-OES, indirect, by difference *The year of the first publication of a standard. 14 Session 4 - Brodmann 7

8 Current and possible new projects of ISO/TC 174 /WG 1 Revision of ISO 9202 (fineness), ISO11596 (sampling) and the 10 standards in on analytical methods. The revised versions should available in the last quarter of this year. Revision of ISO 8654:1987 Colours of gold alloys -- Definition, range of colours and designation. Members expressed the idea of replacing the standards for three-nine purity (999 ) by standards for determining four-nine (999.9 ), as this is the output fineness of refined metals destined for jewellery production. This however, is subject to approval by all participating members of TC Conclusions ISO has published international standards for assaying alloys of gold, silver, platinum and palladium. These standards are used worldwide. ISO/TC 174/WG 1 is revising the majority of its standards for the time being the publication of the revised standards is expected for the forth quarter of New work items, such as e.g. international standards for assaying fine metals of purity, are possible, if the projects find the necessary support within the TC174 s members. Thank you for your time and attention. 16 Session 4 - Brodmann 8

9 Bibliography nical_committee.htm?commid= nical_committee.htm?commid=54074 ISO 9202:1991 Jewellery -- Fineness of precious metal alloys ISO 11210:1995 Determination of platinum in platinum jewellery alloys Gravimetric method after precipitation of diammonium hexachloroplatinate ISO 11426:1997 Determination of gold in gold jewellery alloys Cupellation method (fire assay) ISO 11427:1993 Determination of silver in silver jewellery alloys -- Volumetric (potentiometric) method using potassium bromide ISO 11489:1995 Determination of platinum in platinum jewellery alloys -- Gravimetric determination by reduction with mercury(i) chloride ISO 11490:1995 Determination of palladium in palladium jewellery alloys -- Gravimetric determination with dimethylglyoxime 17 Bibliography continue ISO 11494:2008 Jewellery -- Determination of platinum in platinum jewellery alloys -- Inductively coupled plasma (ICP) solution-spectrometric method using yttrium as internal standard element ISO 11495:2008 Jewellery -- Determination of palladium in palladium jewellery alloys -- Inductively coupled plasma (ICP) solution-spectrometric method using yttrium as internal standard element ISO 11596:2008 Jewellery -- Sampling of precious metal alloys for and in jewellery and associated products ISO 13756:1997 Determination of silver in silver jewellery alloys -- Volumetric (potentiometric) method using sodium chloride or potassium chloride ISO 15093:2008 Jewellery -- Determination of precious metals in 999 gold, platinum and palladium jewellery alloys -- Difference method using inductively coupled plasma optical emission spectroscopy (ICP-OES) ISO 15096:2008 Jewellery -- Determination of silver in 999 silver jewellery alloys -- Difference method using inductively coupled plasma optical emission spectroscopy (ICP- OES) 18 Session 4 - Brodmann 9