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The Dongping gold deposit is located near the center of the northern margin of the North China Craton. It is hosted in the Shuiquangou syenite and characterized by large amounts of tellurides. Numerous studies have addressed this deposit; the mineral paragenesis and ore‐forming processes, however, are still poorly studied. In this contribution, a new mineral paragenesis has been evaluated to further understand ore formation, including sulfides (pyrite, chalcopyrite, galena, sphalerite, molybdenite, and bornite), tellurides (altaite, calaverite, hessite, muthmannite, petzite, rucklidgeite, sylvanite, tellurobismuthite, tetradymite, and volynskite), and native elements (tellurium and gold). Molybdenite, muthmannite, rucklidgeite, and volynskite are reported for the first time in this deposit. We consider the Dongping gold deposit mainly formed in the Devonian, and the ore‐forming processes and the physicochemical conditions for ore formation can be reconstructed based on our newly identified ore paragenesis, that is, iron oxides → (CO2 effervescence) → sulfides → (fTe2/fS2 ratio increase) → Pb‐Bi‐tellurides → (condensation of H2Te vapor) → Au‐Ag‐tellurides → (mixing with oxidizing water) → carbonate and microporous gold → secondary minerals → secondary minerals. The logfO2 values increase from the early to late stages, while the fH2S and logfS2 values increase initially and then decrease. CO2 effervescence is the main mechanism of sulfides precipitation; this sulfidation and condensation of H2Te vapor lead to deposition of tellurides. The development of microporous gold indicates that the deposit might experience overprint after mineralization. The Dongping gold deposit has a close genetic relationship with the Shuiquangou syenite, and tellurium likely originated from Shuiquangou alkaline magmatic degassing. [ABSTRACT FROM AUTHOR]

Japanese brome (Bromus japonicus) has become one of the main weeds in wheat fields in Hebei province of China and causes a large decrease of wheat production. A total of 44 putative resistant and 2 susceptible Japanese brome populations were collected in the 2021/2022 crop season from Hebei province of China to determine resistance levels to flucarbazone‑sodium and to investigate the diversity of acetolactate synthase (ALS) mutations, as well as to confirm the cross-and multiple-resistance levels to ALS and EPSPS (5-enolpyruvate shikimate-3-phosphate synthetase) inhibitors. Whole plant bioassay results showed that 15 out of 44 populations tested or 34% were resistant to flucarbazone‑sodium. The resistance indices of Japanese brome to flucarbazone‑sodium ranged from 43 to 1977. The resistant populations were mainly distributed in Baoding and Shijiazhuang districts, and there was only one resistant population in Langfang district. Resistant Japanese brome had diverse ALS mutations, including Pro-197-Ser, -Thr, -Arg and Asp-376-Glu. The incidence of Pro-197-Ser mutation was the highest at 68%. Application of the CYP450 inhibitor malathion suggested that CYP450 was involved in metabolic resistance in a population without an ALS mutation. The population with Pro-197-Thr mutation evolved weak cross-resistance to mesosulfuron-methyl and pyroxsulam, and it is in the process of evolving multiple-resistance to glyphosate. [Display omitted] • The resistance indices of Japanese brome to flucarbazone-sodium were from 43 to 1977. • ALS mutations of Japanese brome were Pro-197-Ser, -Thr, -Arg and Asp-376-Glu. • Japanese brome evolved cross- and multiple-resistance to ALS and EPSPS inhibitors. [ABSTRACT FROM AUTHOR]

Quartz phenocrysts are common in many granites, volcanic rocks, metamorphic rocks and hydrothermal deposits. The Dongping porphyritic granite contains large amounts of rounded to sub-rounded quartz phenocrysts. Minerals in this porphyritic granite show weak but distinct orientation. Dense clusters of fluid inclusions and albite crystals exist in the quartz, showing snowball texture. Two types of snowball quartz are recognized: (1) large snowball quartz phenocrysts containing large albite grains distributed in the core and small albite grains distributed in the mantle, and (2) small snowball quartz crystals containing small albite grains. The granite is characterized by high SiO 2 (7.15–73.44 wt%), K 2 O (4.70–5.10 wt%) and Na 2 O (4.93–5.21 wt%) contents, low CaO (0.41–0.71 wt%), MgO (0.03–0.05 wt%), Fe 2 O 3 (0.87–0.94 wt%), TiO 2 (0.02–0.03 wt%) and ΣREE (7.10–9.80 ppm) contents. The granite has similar mineral and chemical composition with the aplite in the area, and they were derived from the residual melt of the Shuiquangou magma that suffered assimilation fractional crystallization process. Fluid inclusions in the quartz phenocrysts have homogenization temperatures of 260–380 °C and salinities of 1.4–12.4 wt% NaCl equiv. for liquid + vapor type inclusions and 34.1–44.3 wt% NaCl equiv. for brine ones. The quartz phenocrysts exhibit homogeneous cathodoluminescence without growth bands or zoning. The trace element contents in the quartz phenocrysts are extremely low (Ti 3.4–5.1 ppm, Al 13–118 ppm, Li < 0.1 ppm, Ge < 0.5 ppm) compared to published data of igneous quartz, which may result from the crystallizing conditions of quartz and chemical compositions of the magma. Crystal size distributions (CSD) of albite in quartz show that the snowball quartz formed in two stages, whereby an increase in nucleation and growth rates resulted in the core-mantle texture of quartz phenocrysts. The co-existence of low-, high-salinity and melt inclusions indicates that the quartz phenocrysts crystallized rapidly in a fluid-enriched magma. Magmatic flow led to mineral rotation and resulted in the rounded and sub-rounded shapes of the quartz phenocrysts. Fluid exsolved from the magma raised nucleation and growth rates and resulted in the two types of snowball quartz. Unlabelled Image • The porphyritic granite was derived from the Shuiquangou magma fractionation. • The quartz phenocrysts crystallized rapidly in a fluid-enriched magma. • Magmatic flow led to mineral rotation and rounded shapes of the quartz. • Fluid exsolution leads to the core-mantle texture of the snowball quartz. [ABSTRACT FROM AUTHOR]

• The less porous belt in the microporous gold derives from fluctuations in the fluid. • Gold nucleates at the quartz surface because of catalytic effects or recrystallization. • Petzite could also decompose to microporous gold under hydrothermal conditions. • Hydrothermal fluids are very important in the formation of microporous gold. Microporous gold is common in many Te-Au deposits. Experimental formation and textures of microporous gold have recently been studied. However, few studies have worked on naturally occurring microporous gold. At the Dongping gold deposit, which is one of the most studied Au-Ag-Te deposits in China natural microporous gold is widely distributed in both primary and oxidized ores. This provides a good opportunity to study the textures and the formation of microporous gold in nature. This gold is pseudomorphous in addition to being porous, indicating that it formed via interface coupled dissolution-reprecipitation (ICDR) reactions. Four textures that were not described previously in experiments were observed in samples from this deposit. (1) A hackly interface between the microporous gold and parent calaverite. Te content shows a decreasing trend with increasing distance from the interface. This texture may result from diffusion of excess surface energy as the ICDR reaction moves towards equilibrium. (2) A less-porous band exists in the microporous gold. The band has fewer pores, smaller crystal sizes and similar chemical composition with the surrounding microporous gold. It likely formed due to the fluctuation of the fluid physicochemical conditions (including decreasing temperature, α O2(aq) and increasing pH) that changes the dissolution rate of calaverite. (3) Microporous gold precipitated between quartz and calaverite. As well, gaps developed between gold and remnant calaverite. This texture is derived from catalytic effects of a heterogeneous nucleation or recrystallization process. It is helpful for extraction and aqueous processing of Au-Te ores, and accounts for the phenomenon that quartz can accumulate gold in some hydrothermal gold deposits. (4) Petzite coexists with Ag-bearing microporous gold, indicating that petzite may also decompose to microporous gold under hydrothermal conditions. Calaverite could be dissolved without altered pyrite at high-temperature (>200 °C) conditions, but under weathering conditions, pyrite would be altered first. In primary ores, microporous gold coexists with pyrite and baryte, indicating that it was formed during the late-stage mineralization. In oxidized ores, microporous gold coexists with limonite and baryte, indicating it may have generated during late-stage mineralization and then altered by weathering. Hydrothermal fluids derive from late-stage mineralization may play the main role in the formation of microporous gold compared to weathering processes. This observation also leads us to reappraise the importance of hydrothermal fluids in the weathering dominated ICDR geological processes. [ABSTRACT FROM AUTHOR]