stages of mining tourmaline

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  Tourmalines of Erongo, Namibia | Le Gemmologue

  2018116 · Many of the most extraordinary Namibian tourmalines come from two mines in particular which have acquired almost legendary status: Neu Schwaben and Usakos. Blue-green tourmaline from the Usakos mine. The cut stone weighs over twenty-eight carats and comes from the pocket discovered in 2016. Photo: Prangrak Ruahong.

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  Yellow Mn-Rich Tourmaline from the Canary Mining …

  The Canary mining area was originally worked for electronic-grade quartz (ca. 1982), and the brown tourmaline was tossed into the mine dumps (Njamu, 2003). Yellow tourmaline from eastern Zambia was first documented by Schmetzer and Bank (1983).

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  Europe PMC

  2023727 · Thermally modified tourmaline enhances hydrogen production by influencing hydrolysis acidification in two stages during dark fermentation of corn stover.

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  (PDF) Complexly zoned fibrous tourmaline, Cruzeiro mine, Minas …

  200021 · Abstract and Figures Silver-gray tourmaline fibers intergrown with a deep pink elbaite host from the Cruzeiro mine, Minas Gerais, Brazil, provide evidence for the compositional evolution of ...

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  Genesis of the Xianghualing tin-polymetallic deposit in …

  202331 · Highlights • The formation of the Xianghualing tin deposit can be achieved by (1) fluid-rock interaction, and (2) late-stage magmatic volatile exsolution and cooling. • High oxygen fugacity or acid-consuming reactions are not necessary for cassiterite precipitation. • The evolution of sn-related magmatic-hydrothermal process based on …

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  Delve | Coloured gemstones in eastern DRC: Tourmaline exploitation…

  2020112 · Coloured gemstones in eastern DRC: Tourmaline exploitation and trade in the Kivus Responsible sourcing efforts in the Democratic Republic of Congo (DRC) to date have focused predominantly on the so-called 3TG (tin, tungsten, tantalum and gold) sector. Nevertheless, the artisanal exploitation of other minerals including semi-precious …

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  B- and O-isotopic compositions of tourmaline constrain …

  202016 · the tourmaline-rich assemblages precipitated mostly from magmatic-hydrothermal fluids derived from their host plutons, mixed with minor external components sourced from metasedimentary, meta-ultramafic rocks, and/or meteoric water. The B-isotopic values increase sequentially from tourmaline patches to orbicules and/or cavities in both …

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  Early carbonate veining and gold mineralization in the …

  201861 · Like other deposits in the camp, the gold endowment at the Dome mine is the result of multistage, multi-process mineralization where main stage mineralization occurred towards the end of a period of deformation and magmatism ( Hutchinson, 1993, Goldfarb et al., 2001, Dubé and Gosselin, 2007, Washington, 2008, Washington et al., …

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  TOURMALINE-QUARTZ-CASSITERITE MINERALIZATION OF THE …

  Just Mining District. It is likely that these, and tourmaline-quartz ± rare cassiterite veins of similar orientation across southern Penwith, were formed in response to the same mineralization event. The Nanjizal schorl-cassiterite mineralization is similar to the quartz-tourmaline-cassiterite veins hosted by the Dartmoor Granite.

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