Skarn-type copper-polymetallic rich ore is a unique mineral resource in Tibet and is characterized by numerous diverse elements with high content. The mineral type is mainly sulfide, while the metallogenic ore elements are typically Cu, Pb, Zn, Fe, Ag, Bi, Cd and Co. The use of wet methods to analyze the samples will result in low measurement results due to the high content of silver, lead and other elements, which are difficult to dissolve and precipitate. The analytical results of these samples tend to be on the low side, due to the insoluble and easy-to-precipitate state during the wet pre-treatment caused by the relatively high amount of certain elements. In this study, hydrochloric acid was introduced to pre-desulfurize the ore, followed by dissolution with a mixed acid of nitric, hydrofluoric, and perchloric acid. As a result, the samples can be decomposed completely with effective desulphurization. When the dilution factor was optimized to 1000 and 10% hydrochloric acid was chosen as the solution medium, the sample solution did not precipitate and the multi-element analysis by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) yielded good accuracy and precision. The method measurement ranges are 0.0056% to 20.0% for Cu, 0.0087% to 20.0% for Pb, 0.0031% to 20.0% for Zn, 0.0090% to 20.0% for Fe, 5.40 μg/g to 3000 μg/g for Ag, 10.8 μg/g to 5000 μg/g for Bi, 0.69 μg/g to 5000 μg/g for Cd, 2.09 μg/g to 5000 μg/g for Co, respectively. The method accuracy was less than 5.40% and the precision (RSD,
n=11) was less than 4.41%, which was verified by the national standard reference materials. This method has distinct advantages of simple preliminary treatment, efficient analysis, simultaneous detection of multiple elements, and a wide linear range. The results are in agreement with other methods according to actual sample test analysis.
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