1、BSI Standards PublicationJewellery Determination of precious metals in 999 0/00gold, platinum and palladium jewellery alloys Differencemethod using ICP-OESBS ISO 15093:2015National forewordThis British Standard is the UK implementation of ISO 15093:2015. It supersedes BS ISO 15093:2008 which is with
2、drawn.The UK participation in its preparation was entrusted to TechnicalCommittee STI/53, Specifications and test methods for jewellery and horology.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the n
3、ecessary provisions ofa contract. Users are responsible for its correct application. The British Standards Institution 2015.Published by BSI Standards Limited 2015ISBN 978 0 580 74806 6ICS 39.060Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was
4、 published under the authority of theStandards Policy and Strategy Committee on 31 March 2015.Amendments/corrigenda issued since publicationDate Text affectedBRITISH STANDARDBS ISO 15093:2015 ISO 2015Jewellery Determination of precious metals in 999 0/00gold, platinum and palladium jewellery alloys
5、Difference method using ICP-OESJoaillerie, bijouterie Dosage des mtaux prcieux dans les alliages dor, de platine et de palladium 999 0/00pour la joaillerie, bijouterie Mthode de la diffrence utilisant lICP-OESINTERNATIONAL STANDARDISO15093Second edition2015-02-01Reference numberISO 15093:2015(E)BS I
6、SO 15093:2015ISO 15093:2015(E)ii ISO 2015 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2015All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or pos
7、ting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCase postale 56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copyright
8、iso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 15093:2015ISO 15093:2015(E)Contents PageForeword ivIntroduction v1 Scope . 12 Normative references 13 Principle 14 Sampling 15 Reagents 16 Apparatus . 27 Procedure. 27.1 Sample solution 27.2 Calibration solutions 27.3 Measurement 28 Calculation an
9、d expression of the test results . 38.1 Calibration curves 38.2 Calculation 38.3 Repeatability . 39 Test report . 3Annex A (normative) Wavelengths . 5Bibliography 7 ISO 2015 All rights reserved iiiBS ISO 15093:2015ISO 15093:2015(E)ForewordISO (the International Organization for Standardization) is a
10、 worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represente
11、d on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop th
12、is document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC D
13、irectives, Part 2 (see www.iso.org/directives).Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the dev
14、elopment of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO
15、 specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT), see the following URL: Foreword Supplementary information .The committee responsible for this document is ISO/TC 174, Jeweller
16、y.This second edition cancels and replaces the first edition (ISO 15093:2008), which has been technically revised with following changes: change in Clause 1 that this method is the referee method; addition of a warning in Clause 7 that suitable health and safety procedures should be followed; change
17、 of calibration solutions in 7.2 ; addition of an alternative wavelength for gold in Table A.1; editorial revision of this International Standard.iv ISO 2015 All rights reservedBS ISO 15093:2015ISO 15093:2015(E)IntroductionThe following definitions apply in understanding how to implement an ISO Inte
18、rnational Standard and other normative ISO deliverables (TS, PAS, IWA). “shall” indicates a requirement; “should” indicates a recommendation; “may” is used to indicate that something is permitted; “can” is used to indicate that something is possible, for example, that an organization or individual i
19、s able to do something.ISO/IEC Directives, Part 2 (sixth edition, 2011), 3.3.1 defines a requirement as an “expression in the content of a document conveying criteria to be fulfilled if compliance with the document is to be claimed and from which no deviation is permitted.”ISO/IEC Directives, Part 2
20、 (sixth edition, 2011), 3.3.2 defines a recommendation as an “expression in the content of a document conveying that among several possibilities one is recommended as particularly suitable, without mentioning or excluding others, or that a certain course of action is preferred but not necessarily re
21、quired, or that (in the negative form) a certain possibility or course of action is deprecated but not prohibited.” ISO 2015 All rights reserved vBS ISO 15093:2015Jewellery Determination of precious metals in 999 0/00gold, platinum and palladium jewellery alloys Difference method using ICP-OES1 Scop
22、eThis International Standard specifies an analytical procedure for the determination of either platinum in platinum jewellery alloys, gold in gold jewellery alloys, or palladium in palladium jewellery alloys, with a nominal content of each precious metal of 999 (parts per thousand) by measuring spec
23、ific elements. (See Tables A.1, A.2, and A.3.)This International Standard specifies a method intended to be used as the recommended method for the determination of fineness in 999 alloys covered by ISO 9202.2 Normative referencesThe following documents, in whole or in part, are normatively reference
24、d in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 11596, Jewellery Sampling of precious metal alloys for and in jewellery and
25、 associated products3 PrincipleThe samples of the precious metal alloy are weighed and dissolved in aqua regia to prepare a 10 g/l solution. The impurities are determined by ICP-OES, and the precious metals content is obtained by subtraction of the total content of impurities in the sample from 1 00
26、0 .4 SamplingThe sampling procedure shall be performed in accordance with ISO 11596.5 ReagentsDuring the analysis, unless otherwise stated, use only reagents of recognized analytical grade and only distilled water or water of equivalent purity.5.1 Hydrochloric acid (HCl), approximately 30 % to 37 %
27、HCl (mass fraction).5.2 Nitric acid (HNO3), approximately 65 % to 70 % HNO3(mass fraction).5.3 Aqua regia (should be prepared just before use).Mix three volumes of hydrochloric acid (5.1) and one volume of nitric acid (5.2).5.4 Acid stock solution (may contain both chlorides and nitrates), all relev
28、ant elements (100 mg/l each) in 1 mol/l HCl (5.1) and 1 mol/l HNO3(5.2).INTERNATIONAL STANDARD ISO 15093:2015(E) ISO 2015 All rights reserved 1BS ISO 15093:2015ISO 15093:2015(E)5.5 Reference materials: gold, platinum, or palladium, of 999,9 minimum purity in a suitable form.The content of each impur
29、ity shall be specified.6 Apparatus6.1 Customary laboratory apparatus.6.2 ICP OES, with fixed and/or scanning channels, an optical resolution of 0,02 nm for the relevant elements and a detection limit of 0,05 mg/l or better, and the capability of background correction.For preferably used wavelength,
30、see Annex A.6.3 Analytical balance, with a reading accuracy of 0,01 mg.7 ProcedureWARNING Suitable health and safety procedures should be followed.7.1 Sample solutionFor each sample to be analysed, two sample solutions shall be prepared as follows.Weigh approximately 500 mg of the sample portion to
31、the nearest 0,1 mg, transfer into a 50 ml volumetric flask, and add 30 ml of aqua regia (5.3). Heat gently until complete dissolution of the sample and continue to heat to expel the nitrogen oxides. Allow to cool, make up with water to 50 ml, and mix thoroughly.The deviation in the volume of the vol
32、umetric flask caused by heating is acceptable for this International Standard.If insolubles are observed, dissolution under pressure should be performed.7.2 Calibration solutionsWeigh two portions of (500 2,5) mg of the reference material (5.5) and dissolve each one as specified in 7.1.Blank solutio
33、n. Allow to cool and then make up with water to 50 ml and mix thoroughly.Calibration solution. Allow to cool, add 5 ml of acid stock solution (5.4) or a volume corresponding to the expected amount of the trace element in the matrix to the second reference material solution, make up with water to 50
34、ml, and mix thoroughly.7.3 MeasurementSet up the instrument in accordance with the manufacturers instructions and choose appropriate background correction positions. A clean torch, spray chamber, and sample uptake tubes shall be used and the plasma shall be stabilized before use, following the recom
35、mendations of the instruments manufacturer.Spray the calibration solutions 1 and 2 in accordance with the defined instrument calibration procedure and then run the analytical procedure for the sample solutions. The result shall be displayed with enough decimal places to provide an accurate indicatio
36、n of concentrations at the detection limits of the relevant elements.2 ISO 2015 All rights reservedBS ISO 15093:2015ISO 15093:2015(E)Each solution shall have a stabilization time of at least 30 s, followed by five integrations of at least 5 s each for the determination of the net intensities (i.e. b
37、ackground-corrected).The rinsing time between each measurement shall be sufficient to allow the signal to come back to the baseline, except for the matrix element.The intensity of the chosen matrix line (see Tables A.1, A.2, and A.3) shall not be included in the calculation as described in 8.2.8 Cal
38、culation and expression of the test results8.1 Calibration curvesSet the concentration in the blank solution and the calibration solution, taking into account impurities introduced in the solution by the reference material (5.5) and calculate the calibration curve for each element using the net inte
39、nsities obtained for the blank solution and the calibration solution.8.2 CalculationBy means of the calibration curves (see 8.1), convert the net intensity values into concentration values and use Formula (1) to calculate the mass portion of each relevant element (Wi).WcVmiiss=(1)whereciis the conce
40、ntration of element i in the sample solution, in mg/l;Vsis the volume of the sample solution, in litres;msis the mass of the metallic sample, in milligrams.The detection limit is defined as three standard deviations of the concentration of each individual element measured in the calibration solution
41、.The specific precious metal fineness, Wsp, in parts per thousand, is thus calculated using Formula (2).WWsp i= ()1000 1000 (2)whereWiis the sum of the mass portion of each element found above its detection limit.8.3 RepeatabilityThe results of duplicate determinations shall not deviate more than 0,
42、1 of the precious metal fineness. If the variation is greater than this, the assay shall be repeated.9 Test reportThe test report shall include at least the following information:a) identification of the sample including source, date of receipt, and form of sample;b) sampling procedure;c) the method
43、 used by reference to this International Standard, i.e. ISO 15093; ISO 2015 All rights reserved 3BS ISO 15093:2015ISO 15093:2015(E)d) precious metals content of the sample, in parts per thousand () by mass, as single values and mean values, with the result reported with four significant figures;e) i
44、f relevant, any deviations from the method specified in this International Standard;f) any unusual features observed during the determination;g) date of test;h) identification of the laboratory carrying out this analysis;i) signature of the laboratory manager and operator.4 ISO 2015 All rights reser
45、vedBS ISO 15093:2015ISO 15093:2015(E)Annex A (normative) WavelengthsOther wavelengths than those specified in Tables A.1, A.2, and A.3 may be used. In all cases, attention shall be paid to spectral interferences. These tables are not exhaustive. If other elements are present, they shall be analysed.
46、Table A.1 PlatinumElementWavelength nmAlternative nmElementWavelength nmAlternative nmAg 328,068 Ni 352,454 231,604Au 242,795 267,595 Pb 168,220 220,353Bi 223,061 Pta224,552 273,396Cd 226,502 Pd 340,458 355,308Co 228,616 238,892 Rh 343,489 Cu 324,754 Ru 240,272 Fe 259,94 Sn 189,989 Ir 215,278 Ti 334
47、,941 Mn 257,610 Zn 213,856 aSuggested matrix line (see 7.3).Table A.2 GoldElementWavelength nmAlternative nmElementWavelength nmAlternative nmAg 328,068 Ni 352,454 231,604Aua389,789 302,920 Pb 168,220 220,353Bi 223,061 Pd 340,458 355,308Cd 228,802 226,502 Pt 306,471 203,646Co 228,616 238,892 Rh 343,
48、489 Cu 324,754 Ru 240,272 Fe 259,94 Sn 189,989 189,927Ir 215,278 Ti 334,941 Mn 257,610 Zn 213,856 aSuggested matrix line (see 7.3). ISO 2015 All rights reserved 5BS ISO 15093:2015ISO 15093:2015(E)Table A.3 PalladiumElementWavelength nmAlternative nmElementWavelength nmAlternative nmAg 328,068 Ni 352
49、,454 231,604Au 242,795 Pda248,892 229,651Bi 223,061 Pt 306,471 203,646Cd 228,802 226,502 Pb 220,353 Co 228,616 238,892 Rh 343,489 Cu 324,754 Ru 240,272 Fe 259,94 Sn 189,989 189,927Ir 215,278 Ti 334,941 Mn 257,610 Zn 213,856 aSuggested matrix line (see 7.3).6 ISO 2015 All rights reservedBS ISO 15093:2015ISO 15093:2015(E)Bibliography1 ISO 9202, Jewellery Fineness of precious metal alloys ISO 2015 All rights reserved 7BS
