Raman Spectrum Characteristic of Associated Minerals of Turquoise from Mongolia

Turquoise from Mongolia is rich in associated minerals. The relative density of the turquoise samples from Mongolia determined by hydrostatic weighing is between 2.433~2.743 g/cm³. The sample with kaolinite has lower relative density and loose texture, while other samples are homogeneous. Raman spectrometer, electron probe microanalysis and infrared spectrometer were used to determine the associated minerals, which include albite, quartz, jarosite, muscovite, zircon, goethite, rutile, anatase, pyrite, pyrrhotite, chalcopyrite, and carrollite. The chemical compositions of jarosite was determined by electron probe microanalysis with the results (K_0.393Na_0.300Ba_0.099Fe_0.076²⁺Sr_0.030)_∑=0.898(Fe_3.087³⁺Al_0.061) _∑=3.148 (S_1.681P_0.273) _∑=1.954 O₈(OH)₆. The infrared vibration of white paragenetic minerals fingerprint area was matching with kaolinite. The existence of carrollite in associated minerals can be used as one of the characteristics to determine the turquoise origin of Mongolia.