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In this study, in order to protect the characteristic Dendrobium devonianum Paxt industry in the Longling area, and promote the healthy development of its characteristic Chinese herbal medicines in Yunnan Province, China, the identification of Dendrobium devonianum Paxt and Dendrobium officinale Kimura et Migo from Longling county was discussed using time of flight mass spectrometry. The data of 13 Dendrobium devonianum and 7 Dendrobium officinale in the Longling area were collected by TOF MS-IDA-15 MS/MS mode, and the collected data were analyzed by PCA and T-test using MarkerView software, and the difference markers were searched using the database to confirm their compound structures. In positive and negative ion modes, 3645 and 2344 peaks were detected, respectively; 64 positive ion compounds and 60 negative ion compounds, for a total of 124 compounds were identified, mainly including organic acids, polyphenols, alkaloids, amino acids and their derivatives, benzene and its derivatives, and other compounds. The score plot and loading plot analyzed by PCA show that Dendrobium devonianum and Dendrobium officinale collected in the Longling area can be effectively identified and differentiated by high-resolution mass spectrometry with the 15 different markers in positive ion mode and 17 markers in negative ion mode, respectively. The successful identification of Dendrobium devonianum and Dendrobium officinale fully demonstrates that TOF MS can be effectively used in the identification of Dendrobium and related Chinese herbal medicines with broadly application foreground. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Bainiuchang Ag-Sn-polymetallic deposit contains economic indium mineralization. • Sphalerite is the most important indium-bearing mineral in the Bainiuchang deposit. • 2Zn2+↔Cu++In3+ and/or 3Zn2+↔Ag++Sn2++In3+ are the most plausible substitution mechanisms for indium into sphalerite. • Indium reserves of ore deposits are controlled to some extent by nature of granitic magmas. The Bainiuchang Ag–Sn–polymetallic deposit is located in the world-calss Southeast Yunnan Indium Metallogenic Belt (SYIMB). The deposit contains approximately 1000 tons of In, but the mechanisms of mineralization and hosts of In in this deposit remain unclear. To clarify these ambiguities, we carried out fieldwork, major- and trace-element analyses of In-bearing minerals, and cassiterite and zircon U–Pb geochronology. Five ore zones were identified, which, from contact of the granitic intrusion upwards, are the In-poor magnetite–cassiterite ore zone, the In-poor Cu ore zone, the In-rich Zn–Sn ore zone, the In-rich Sn–Pb–Zn ore zone, and the In-poor Pb–Zn ore zone. Cassiterite and zircon U–Pb geochronology demonstrate that mineralization at Bainiuchang occurred at ca. 85.80±0.45 Ma (MSWD = 1.5), which is similar to the 85.34±0.42 Ma (MSWD = 1.7) age of the granitic intrusion. This temporal relationship suggests that there is a genetic link between In mineralization and granitic magmatism in this deposit. Ore petrography and mineral chemical analyses indicate that sphalerite, chalcopyrite, and stannite are main In-bearing minerals. From a mass balance perspective, sphalerite is the most important In-bearing mineral, accounting for ∼85% of the In budget at Bainiuchang. Indium is incorporated into sphalerite via the coupled substitution 2Zn2+ ↔ Cu+ + In3+ and/or 3Zn2+ ↔ Ag+ + Sn2+(+In3+). Two generations of sphalerite occur in the deposit, SpI and SpII, which formed during the cassiterite–sulfide and carbonate–sulfide stages, respectively. Based on textural relationships, SpI is further subdivided into SpIa, SpIb, and SpIc. These temporally and texturally distinct sphalerite have variable In contents, with SpIa having the highest In content (0.08–0.44 wt%), followed by SpIb (0.02–0.39 wt%), SpIc (187–236 ppm), and SpII (0.64–7.14 ppm). It is suggested here that the variations in In contents of the sphalerite reflect the evolution of the magmatic–hydrothermal fluids from which the sphalerite precipitated under different f S 2 and temperature. By comparing the Bainiuchang deposit to other In-bearing deposits in the southwestern Yangtze Block, it is evident that that the nature and source of the associated granites, and the degree of fractionation of the granitic magmas are likely important controls on In mineralization in the SYIMB and other regions. [ABSTRACT FROM AUTHOR]