BS ISO 15093:2020 pdf free.Jewellery and precious metals —Determination of high purity gold, platinum and palladium—Difference method using ICP-OES.
BS ISO 15093 1 Scope This document specifies the analytical procedure for the determination of gold, platinum and palladium with a nominal content of and above 999 %o [parts per thousand]. This document specifies a method intended to be used as the recommended method for the determination of gold, platinum and palladium of fineness of and above 999 %o. For the determination of fineness of and above 999,9 %o, modifications described in Annex B apply. 2 Normative references The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. 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一Sampling of precious metal alloys for and in jewellery and associated products 3 Terms and definitions No terms and definitions are listed in this document. ISO and IEC maintain terminological databases for use in standardization at the following addresses: 一ISO Online browsing platform: available at http://www.iso.org/obp 一IEC Electropedia: available at http://www.electropedia.org/ 4 Principle The sample is weighed and dissolved in aqua regia to prepare a 10 g/l solution (higher concentration is used for fineness of and above 999,9 %o]. The impurities are determined by ICP-OES (see Table A.1 for wavelengths), and the precious metal content is obtained by subtraction of the total content of impurities in the sample from 1 000 %o. For the determination of fineness of and above 999,9 %o,  modifications described in Annex B shall be applied. Set up the instrument in accordance with the manufacturer’s 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 recommendations of the instruments manufacturer.Spray the blank and calibration solutions 1 (8.3.2) and 2 8.3..3) 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 indication of concentrations at the detection limits of the relevant elements. Each solution shall have a stabilization time of at least 30 s, followed by at least three integrations each for the determination of the net intensities (background-corrected). The rinsing time between each measurement shall be sufficient to allow the signal of each impurity to come back to the baseline.BS ISO 15093 pdf download.