 | | Journal (article/letter/editorial) | | ARTICLE Source of boron in the Palokas gold deposit, northern Finland: evidence from boron isotopes and...recently discovered Palokas gold deposit is part of the larger Rompas-Rajapalot gold-mineralized system...Peräpohja Belt, northern Finland. Tourmaline is an important gangue mineral in the Palokas gold mineralization...composition of tourmaline from three areas: (1) the Palokas gold mineralization, (2) a pegmatitic tourmaline...alkaligroup tourmaline and can be classified as dravite and schorl. The δ11B values of the three localities |  | Hartmann, Léo A., Werle, Mariana, Michelin, Cassiana R.L., Lana, Cristiano, Queiroga, Gláucia N., Castro, Marco P., Arena, Karine R. (2019) Proto-Adamastor ocean crust (920 Ma) described in Brasiliano Orogen from coetaneous zircon and tourmaline. Geoscience Frontiers, 10 (4) 1623-1633 doi:10.1016/j.gsf.2018.09.018 | Journal (article/letter/editorial) | | composition (e.g., U/Yb < 0.1). Tourmaline is dravite with d11B ¼ þ1.8& (Tur 1), 0& (Tur 2), 8.5& (Tur...Tourmaline is dravite and zircon has ‘oceanic’ composition, 3 Hf(920 Ma) ¼ þ12 and HfTDM ¼ 1.0 Ga. Dravite from...tourmaline and chlorite EPMA analyses display dravite compositions for all three zones and little variation...Nakamura, 2001), as presently observed. Studied dravite has three different zones in BSE images, chemistry...Figure 11. Boron isotopic composition of Bossoroca dravite and boron reservoirs. Field of selected continental |  | | Journal (article/letter/editorial) | | tourmalines belong to the alkali group and to the dravite-schorl solid solution. Type III tourmaline which...0.17 Dravite Dravite Dravite Schorl Dravite Dravite Dravite Dravite Dravite Dravite Dravite...Dravite Dravite Dravite Dravite Dravite Dravite Dravite Dravite Dravite Dravite Dravite Dravite...Dravite Dravite Sample NO. XBD 22b XBD 22c XBD 22e XBD 22f XBD 22g XBD 22h XBD 22e XBD 22f XBD 22g...Schorl Dravite Dravite Dravite Dravite Dravite Dravite Dravite Dravite Dravite Dravite Dravite |  | | Journal (article/letter/editorial) | | compositions. All tourmalines are close to the dravite endmember and belong to the alkali group. The type-I...M., Hawthorne, F.C., Ottolini, L., 2011. Fluor-dravite, NaMg3Al6Si6O18(BO3) (3)(OH)(3)F, a new mineral..., 2017. Source of boron in the Palokas gold deposit, northern Finland: Evidence from boron isotopes and |  | | Journal (article/letter/editorial) | | □/(Na+□) apfu (Fig. 9c, d), belongs mainly to the dravite-schorl group (65 – 17% on average), with minor...compositional homogeneity of the analyzed tourmaline (dravite-rich type, Mg# [Mg/(Mg+Fe)] = 0.80) (Fig. 9) supports...pegmatite, Orivesi, southern Finland. Bulletin of Geological Society of Finland 60(1), 7-43. Larsen, E.S..., 2017. Source of boron in the Palokas gold deposit, northern Finland: evidence from boron isotopes and...000 31.000 31.000 31.000 End members calculation dravite 61.53 61.53 66.12 67.16 65.55 64.69 63.74 67.54 |
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