A Comparative Study On The Mineralogy Of Burmese Jadeite Gemstones

At present,the index of the jadeite origin is traceable with the indicator of the adverse identification,lacks intelligent judgment means,and the collection and choice of the selection of sequential characteristics of the origin,the production area is not high,and it is urgent to establish an jadeite identification technology based on spectral characteristics.Therefore,in order to achieve the rapid and accurate origin of Myanmar's jadeite,this thesis is compared with the main gemmatics of Myanmar's mainland jadeite,establishing an intelligent identification model to efficient,simple,lossless,and objective identification of jadeite producers.important meaning.This article selection Burmese Damuka,Longken,Pharkant three typical scene jadeite stone 24 samples as research objects,using a polarized microscope,Fourier infrared spectrometer,X-ray fluorescence spectrometer,laser Raman spectrometer,Fisher discrimination analysis And artificial neural network model analysis,analysis and research on its chemical composition,texture and structure,spectral characteristics,and based on molecular spectroscopy,using principal component analysis and artificial neural network to establish a production site discrimination model,and Its discrimination effect is tested.Got the following results:1.The main mineral composition of the three areas of Myanmar is in crystalloblastic texture,consisting mainly of jadeite mineral,and the structure is mostly granoblastic crystalloblastic texture,which is mainly based on a granular transcamination structure;some samples visible fragmentation,and the residual structure is interrupted.2.The n _NA/(n _NA+n _Ca)of the three areas samples in Myanmar is greater than 0.8,which are hard jadeite,and the Si O₂content is in the range of 56%to 60.5%,and the Na₂O content is in the range of 10%to 17%.The Al₂O₃content is in the range of 22%to 25.5%.3.The infrared spectrum in the three areas of Myanmar is mainly vibration absorption caused by oxygen(M-O)group and metal cation(M₁,M₂);Si-O-Si,O-Si-O vibration is caused;A wide absorption band having a wide absorption band in four bands of 600?400cm^-1,800?600cm^-1,800?950cm^-1,1200?950cm^-1,consistent with the hard jadeite standard infrared spectroscopy.jadeite near infrared spectrum absorption peaks mainly H₂O vibration combined and multiplier,mainly showing M-OH vibration absorption peaks with weaker intensity of 4530cm^-1,5229cm^-1H₂O telescopic vibration and curved vibration combined frequency absorption belt,7071cm^-1water molecular telescopic vibration first stage multiplier absorption peak.4.The three of Myanmar has a tapered characteristic Raman spectrum,which is mainly expressed as(Si-O_br-Si),non-bridge oxygen(Si-O_nb1-Al)and(Si-O_nb2-Al)vibration absorption peaks.The main peak is 1046,995,878,787,706,585,531,442,382,318,265,212 cm^-1.5.The PCA-BP Neural Network Model Training Group based on infrared spectroscopy is 81.2%.The total sample of the total sample of the test group is 100%;the accurate judgment rate based on the Raman spectroscopy combined with the PCA-BP neural network training group is 83.1%,and the inspection team is discriminating The correct rate is 100%,and the model is higher than the comprehensive accuracy of the three origins of Myanmar.This method is applied to Russia,Myanmar,Guatemala,and the infrared spectroscopy combined with PCA-BP neural network discriminant model of training samples.The comprehensive discrimination accuracy rate is 94.2%,and the accuracy of the test sample is 91.6%.The Training Group Comprehensive Discriminant Accreditation is 93.48%in the PCA-BP Neural Network Discriminant Model,and the accuracy of the test group is100.0%.It indicated that the PCA-BP neural network analysis was applied to jadeite Origin Rapid Identification with a certain practicality and feasibility.