Foreword

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This document was prepared by Technical Committee ISO/TC 174, Jewellery and precious metals.

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1 Scope

This document specifies an analytical method for the determination of silver on a material considered homogeneous. The silver content of the samples lies preferably between 50 ‰ (parts per thousand) and 990 ‰ (parts per thousand). Fineness above 990,0 ‰ can be determined using a spectroscopy method by difference (see ISO 15096 ).

NOTE Lower contents of silver can be analysed according to this method.

2 Normative references

3 Terms and definitions

4 Principle

5 Reagents

5.1

5.2

5.3

5.4

5.5

6 Apparatus

6.1

6.2

6.3

6.4

6.5

6.6

7 Sampling

8 Procedure

8.1 Internal standard solutions

8.2 Calibration solutions

8.3 Sample solutions

8.4 Measurement

9 Calculation and expression of results

9.1 Calculation

9.2 Repeatability

10 Test report

Bibliography