Abstract：Triplite is a rare mineral，and gem-grade triplite can present a highly saturated reddish orange. In this paper，three samples from Pakistan are selected for systematic research through Electron Microprobe，Raman spectra，Infrared spectra and UV-Vis absorption spectra. The purpose is to obtain their chemical composition and spectral characteristic，analyze the chromogenic ions，and provide important data for their species identification and optimization processing. The chemical formula of average chemical composition is (Mn1.66, Fe0.17, Ca0.15, Mg0.03)Σ2.02P0.99O4.14(F)0.82，which belongs to the Mg-rich and Fe-poor triplite. And it has a similar chemical composition with the gem-grade triplite produced in the Shigar Valley of Pakistan in the literature. Raman spectra and Infrared spectra show that the main vibration group of triplite is PO3-4 group. The main peak of Raman spectra is located at 980 cm-1，which can be used to analyze the substitution relationship between OH- and F. The intensity contrast of the 450 and 427 cm-1 bimodal peaks can reflect the substitution relationship between Mn2+ and Fe2+. The Infrared spectra has absorption peaks in the 400～650 and 900～1 200 cm-1 band，which can reflect the substitution relationship between OH- and F, Mn2+ and Fe2+. Thus，Raman spectra and Infrared spectra can be used to clearly distinguish the isomorphic minerals：triplite，wolfeite and zwieselite. In the UV-Vis absorption spectra，the strong absorption peak centered at 406 nm is caused by the spin-forbidden transition of Mn2+. The weak absorption peak centered at 455 nm is caused by the spin-forbidden transition of Fe2+，and Mn2+ also has a certain effect on this peak. The absorption peak centered at 533 nm is caused by the transition of Mn2+，6A1g(S)→4T1g(G). So the samples show a reddish orange color，which is an idiochromatic mineral. There are common isomorphisms in the triplite group minerals. Raman spectra and Infrared spectra can identify triplite accurately，and EMPA can provide important information for the traceability of its origin.
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