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The Weilasituo Li–polymetallic deposit, located on the western slope of the southern Great Xing’an Range in the eastern Central Asian Orogenic Belt, is hosted by quartz porphyry with crypto-explosive breccia-type Li mineralisation atop and vein-type Sn-Mo-W-Zn polymetallic mineralisation throughout the breccia pipe. This study introduces new data on multistage quartz and mica in situ trace elements; the study was conducted using laser ablation inductively coupled plasma mass spectrometry and 40Ar/39Ar dating of zinnwaldite to delineate the metallogenic age and genesis of Li mineralisation. Zinnwaldite yields a plateau age of 132.45 ± 1.3 Ma (MSWD = 0.77), representing Early Cretaceous Li mineralisation. Throughout the magmatic–hydrothermal process, quartz trace elements showed Ge enrichment. Li, Al, and Ti contents decreased, with Al/Ti and Ge/Ti ratios increasing, indicating increased magmatic differentiation, slight acidification, and cooling. Mica’s rising Li, Rb, Cs, Mg, and Ti contents and Nb/Ta ratio, alongside its falling K/Rb ratio, indicate the magma’s ongoing crystallisation differentiation. Fractional crystallisation primarily enriched Li, Rb, and Cs in the late melt. Mica’s high Sc, V, and W contents indicate a high fO2 setting, with a slightly lower fO2 during zinnwaldite formation. Greisenisation observed Zn, Mg, and Fe influx from the host rock, broadening zinnwaldite distribution and forming minor Zn vein orebodies later. Late-stage fluorite precipitation highlights a rise in F levels, with fluid Sn and W levels tied to magma evolution and F content. In summary, the Weilasituo Li–polymetallic deposit was formed in an Early Cretaceous extensional environment and is closely related to a nearby highly differentiated Li-F granite. During magma differentiation, rare metal elements such as Li and Rb were enriched in residual melts. The decrease in temperature and the acidic environment led to the precipitation of Li-, Rb-, and W-bearing minerals, and the increased F content in the late stage led to Sn enrichment and mineralisation. Fluid metasomatism causes Zn, Mg, and Fe in the surrounding rock to enter the fluid, and Zn is enriched and mineralised in the later period.

Eastern Tianshan hosts a number of porphyry Cu deposits. However, these mainly formed in the Jueluotage Belt, in the middle part of Eastern Tianshan. The Tonggou porphyry Cu mineralization is an exception to this, since it is located in the Bogda Orogenic Belt, north of Eastern Tianshan. We obtained new zircon U-Pb ages, whole-rock geochemical data, zircon Hf isotope data, and zircon trace element compositions. LA-ICP-MS zircon U-Pb dating indicates a crystallization age of 302.2–303.0 Ma for the Tonggou mineralized granodiorite (TMG), which suggests that the Tonggou porphyry Cu mineralization formed in the Late Carboniferous period. εHf (t) data (1.8–14.1) for TMG suggests it was sourced from juvenile crustal melts, mixed with some mantle materials. TMG displays low ΣREE, compatible elements (Ba, Sr, Zr, and Hf), Zr/Hf and Nb/Ta ratios, as well as clearly negative Eu anomalies in whole rocks analyses. In addition, TMG is enriched in P, Hf and Th/U ratios in zircon, and has lower crystallization temperatures (734 to 735 °C) than the Daheyan barren granodiorite (DBG) (753 to 802 °C). Whole rock and zircon geochemical analyses show that the TMG was formed by fractional crystallization to a greater extent than the DBG in the Bogda Orogenic Belt. Moreover, zircon grains of the TMG show high Ce4+/Ce3+ ratios (159–286), which are consistent with related values from large porphyry deposits of the Central Asian Orogenic Belt (CAOB). High Ce4+/Ce3+ ratios reflect oxidizing magmas as a result of fractional crystallization, which indicates that the Tonggou deposit has potential to host a large porphyry Cu deposit.

The Qibaoshan polymetallic ore field is located in the Wulian area, Shandong Province, China. Four ore deposits occur in this ore field: the Jinxiantou Au−Cu, Changgou Cu−Pb−Zn, Xingshanyu Pb−Zn, and Hongshigang Pb−Zn deposits. In the Jinxiantou deposit, three paragenetic stages were identified: quartz−pyrite−specularite−gold (Stage 1), quartz−pyrite−chalcopyrite (Stage 2), and quartz−calcite−pyrite (Stage 3). Liquid-rich aqueous (LV type), vapor-rich aqueous (V type), and halite-bearing (S type) fluid inclusions (FIs) are present in the quartz from stages 1−3. Microthermometry indicates that the initial ore-forming fluids had temperatures of 351−397 °C and salinities of 42.9−45.8 mas. % NaCl equivalent. The measured hydrogen and calculated oxygen isotopic data for fluid inclusion water (δ18OFI = 11.1 to 12.3‰; δDFI = −106.3 to −88.6‰) indicates that the ore-forming fluids were derived from magmatic water; then, they were mixed with meteoric water. In the Changgou deposit, three paragenetic stages were identified: quartz−pyrite−specularite (Stage 1), quartz−pyrite−chalcopyrite (Stage 2), and quartz−galena−sphalerite (Stage 3). LV, V, and S-type FIs are present in the quartz from stages 1−3. Microthermometry indicates that the initial ore-forming fluids had temperatures of 286−328 °C and salinities of 36.7−40.2 mas. % NaCl equivalent. The measured hydrogen and calculated oxygen isotopic data for fluid inclusion water (δDFI = −115.6 to −101.2‰; δ18OFI = 12.2 to 13.4‰) indicates that the ore-forming fluids were derived from magmatic water mixed with meteoric water. The characteristics of the Xingshanyu and Hongshigang deposits are similar. Two paragenetic stages were identified in these two deposits: quartz−galena−sphalerite (Stage 1) and quartz−calcite−poor sulfide (Stage 2). Only LV-type FIs are present in the quartz in stages 1−2. The ore-forming fluids had temperatures of 155−289 °C and salinities of 5.6−10.5 mas. % NaCl equivalent. The measured hydrogen and calculated oxygen isotopic data for fluid inclusion water (δDFI = −109.8 to −100.2‰; δ18OFI = 10.2 to 12.1‰) indicates that the ore-forming fluids were derived from circulating meteoric waters. The sulfur isotopes (δ34Ssulfide = 0.6 to 4.3‰) of the four deposits are similar, indicating a magmatic source for the sulfur with minor contributions from the wall rocks. The ore field underwent at least two phases of mineralization according to the chronology results of previous studies. Based on the mineral assemblage and fluid characteristics, we suggest that the late Pb−Zn mineralization was superimposed on the early Cu (−Au) mineralizaton in the Changgou deposit.

The Jinchang gold deposit is located in the eastern Yanji–Dongning Metallogenic Belt in Northeast China. The orebodies of the deposit are hosted within granite, diorite, and granodiorite, and are associated with gold-mineralized breccia pipes, disseminated gold in ores, and fault-controlled gold-bearing veins. Three paragenetic stages were identified: (1) early quartz–pyrite–arsenopyrite (stage 1); (2) quartz–pyrite–chalcopyrite (stage 2); and (3) late quartz–pyrite–galena–sphalerite (stage 3). Gold is hosted predominantly within pyrite. Pyrite separated from quartz–pyrite–arsenopyrite cement within the breccia-hosted ores (Py1) yield a Re–Os isochron age of 102.9 ± 2.7 Ma (MSWD = 0.17). Pyrite crystals from the quartz–pyrite–chalcopyrite veinlets (Py2) yield a Re–Os isochron age of 102.0 ± 3.4 Ma (MSWD = 0.2). Pyrite separated from quartz–pyrite–galena–sphalerite veins (Py3) yield a Re–Os isochron age of 100.9 ± 3.1 Ma (MSWD = 0.019). Re–Os isotopic analyses of the three types of auriferous pyrite suggest that gold mineralization in the Jinchang Deposit occurred at 105.6–97.8 Ma (includes uncertainty). The initial 187Os/188Os values of the pyrites range between 0.04 and 0.60, suggesting that Os in the pyrite crystals was derived from both crust and mantle sources.