ISO 23345:2021 宝飾品および貴金属—ED-XRFによる非破壊貴金属の細かさの確認 | ページ 2

Foreword

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

Introduction

This document describes a non-destructive method to verify (confirm) the fineness of finished and semifinished jewellery items considered homogeneous by ED-XRF (energy-dispersive X-ray fluorescence).

Multiple methods are available to determine the fineness of precious metal alloys. They however are all requiring the destruction of the sample and long analysis time; for example gold cupellation by ISO 11426. Under some circumstances, destruction of the sample is not an option. This method proposes a non-destructive alternative, which allows validating a declared fineness.

The standard is not suitable for the regulatory hallmarking application. Because of the inherent higher uncertainty associated with ED-XRF measurements, some results might be inconclusive.

The document gives guidelines on the

• instrumentation,
• number and composition of calibration standards needed for calibration,
• composition of reference material needed to verify the calibration,
• number of measurement and replicates on the sample whose fineness is to be verified
• uncertainty calculation, and
• interpretation of the results.

1 Scope

This document describes a non-destructive method to verify (confirm) the precious metal fineness of finished and semifinished jewellery item(s) considered homogeneous by ED-XRF (energy dispersive X-ray fluorescence), including alloys according to ISO 9202.

This document is not suitable for any coated items. WD-XRF (wavelength dispersive X-ray fluorescence) equipment cannot be used.

2 Normative references

There are no normative references in this document.

3 Terms and definitions

For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

Bibliography