Boron isotope composition of coexisting tourmaline and hambergite in alkaline and granitic pegmatites

Geochemical and Boron Isotopic Evidence that Tourmaline Records Country Rock Assimilation of Leucogranites in the Himalayan Orogen

“…However, in contrast to the relatively primary TMG, many of the highly evolved leucogranites may have undergone assimilation of country rocks, which can modify wholerock geochemical and isotopic characteristics (Zeng et al, Geochemical and Boron Isotopic Evidence that Tourmaline Records Country Rock Assimilation of Leucogranites in the Himalayan Orogen 2019). Tourmaline B isotopic compositions of leucogranites and pegmatites have commonly been used as an isotopic tracer (e.g., Jiang et al, 1998Jiang et al, , 2003Trumbull et al, 2013;Yang et al, 2015;Gou et al, 2017;Maner et al, 2017;Zhao et al, 2019;Zhou et al, 2019;Duan et al, 2020;Sunde et al, 2020). As such, it is important to assess if tourmaline is affected by late-stage crustal assimilation.…”

¹⁰Be/⁹Be ratios of phenakite and beryl measured via direct Cs sputtering: Implications for selecting suitable Be carrier minerals for the measurement of low-level ¹⁰Be

“…Oftedal (1964) recorded 1000 µg/g of B in phenakite from Kragerø, Norway, whereas there was no B in beryl from Tørdal, Norway. The higher B concentration in phenakite might be attributed to the fact that B is an incompatible element (Sunde et al, 2020). It can also be attributed to the relatively late occurrence of phenakite crystallization compared with that of beryl ( Černý, 2002).…”

Tourmaline occurrence and gold mineralization at a granitoid-metasediment contact in the Upper Lom Basin, east Cameroon

“…Tourmaline chemical composition can provide exploitable information on the source and evolution of ore fluid [2,[7][8][9], including possible fingerprints on the origin of associated gold mineralization [10]. The elemental composition of tourmaline, including boron isotopic data, have been widely employed in studies aimed at unraveling: (1) The source of the boron, (2) Fluid-rock interaction processes and transport, (3) The evolution of the magmatic fluid, (4) Temperature of the fluids related to B-metasomatism, and (5) The influence of magmatic-hydrothermal process on formation of orogenic gold deposits and the timing of magmatic, metamorphic and hydrothermal processes [1,5,6,[11][12][13][14]. The relative abundance of δ 11 B in nature [~ 60%; 5] makes the boron isotope system a valuable tracer of boron source in magmatic-hydrothermal and metamorphic systems [14].…”

“…The elemental composition of tourmaline, including boron isotopic data, have been widely employed in studies aimed at unraveling: (1) The source of the boron, (2) Fluid-rock interaction processes and transport, (3) The evolution of the magmatic fluid, (4) Temperature of the fluids related to B-metasomatism, and (5) The influence of magmatic-hydrothermal process on formation of orogenic gold deposits and the timing of magmatic, metamorphic and hydrothermal processes [1,5,6,[11][12][13][14]. The relative abundance of δ 11 B in nature [~ 60%; 5] makes the boron isotope system a valuable tracer of boron source in magmatic-hydrothermal and metamorphic systems [14]. There is a plexus of views on the source of fluid and metals in hydrothermal and orogenic gold deposits based on the interpretation of δ 11 B isotopic data and the geologic setting of such gold deposits in the world [15].…”