Quantitative Analysis Of Polymineral Jade Based On Calcite/Serpentine/Tremolite By Infrared Spectroscopy

In the detection of jewelry and jade,we often encounter a variety of mineral symbiotic products of jade,and the naming of jade is directly related to the minerals and their contents.And the quality evaluation of some jades is also related to the kinds and contents of the minerals they contain,so it is very important to establish the quantitative analysis model of the corresponding minerals in the jades for the naming and quality evaluation of the jades.In this paper,pure calcite,serpentine and tremolite powders are used as raw materials to simulate the composition of Polymineral jade.Then the samples are analyzed by infrared spectroscopy,and the infrared spectra of minerals with different contents are obtained.The infrared spectra obtained were analyzed by origin software,and the characteristic absorption peaks and corresponding absorbance A values of minerals were determined.Then the data were fitted by MATLAB and 1stopt software,and the corresponding quantitative analysis model of minerals was obtained.Through the analysis and verification of three mixed samples of calcite-serpentine,tremolite-serpentine and tremolite-calcite-serpentine,the quantitative analysis models of three mineral components of calcite,serpentine and tremolite were established respectively.The model shows that the relationship between the content of these three minerals and the absorbance conforms to Lambert-Beer law.The purity of samples,particle size and thickness of tablets have a great influence on the establishment of quantitative analysis model.Therefore,in the preparation of samples,we must strictly observe the operation process and precisely control the experimental conditions.In addition,the conditions for infrared spectrometer to collect spectra should be unified.Baseline drawing will have an impact on the establishment of mineral quantitative analysis model.In addition,the same mineral may have multiple characteristic absorption peaks.Quantitative analysis models are established for different characteristic absorption peaks.The correlation coefficients of these models are close to 1.Therefore,for different characteristic absorption peaks of minerals,quantitative analysis models can beestablished.The contents of calcite,serpentine and tremolite in the validated samples were calculated by using the three models.The error between the calculated results and the actual content is between 1.17% and 5.79%,averaging 3.4%.The results show that the quantitative analysis model can be applied to the quantitative analysis of the mineral components as long as there is no superposition or other influence between the absorption peak of the symbiotic mineral and the characteristic peak of the model mineral.