Boron isotope composition of tourmalinite and vein tourmalines associated with gold mineralization, Serra do Itaberaba Group, central Ribeira Belt, SE Brazil

Discriminating fluid source regions in orogenic gold deposits using B-isotopes

“…It is for these reasons that the use of stable B-isotopes in tourmaline has become well established in the study of ore deposits (e.g. Palmer and Slack, 1989;Xavier et al, 2008;Garda et al, 2009;Slack and Trumbull, 2011;Tornos et al, 2012;Duncan et al, 2014;Molnár et al, 2016). While boron isotope analysis by thermal ionization mass spectrometry (TIMS) requires complete chemical dissolution of a bulk tourmaline sample, secondary ion mass spectrometry (SIMS) allows for texturally resolved measurement of δ 11 B in tourmaline at levels of precision that allow detailed analysis of fluid source reservoirs in relation to the mineral paragenesis.…”

Boron isotopic constraints on the Nb and Ta mineralization of the syenitic dikes in the ~ 260 Ma Emeishan large igneous province (SW China)

“…It is thus unlikely that there was a substantial fractionation of sodalite during the formation of the Nb-Ta-mineralized and Nb-Ta-poor syenitic dikes. The Nb-Ta-mineralized and Nb-Ta-poor syenitic dikes and syenitic plutons in the Panxi region have δ 11 B values similar to those of terrestrial sediments, far below the value of seawater and/or fluid (Garda et al, 2009) (Fig. 10b).…”

The Inventory of Geological Heritage of the State of São Paulo, Brazil: Methodological Basis, Results and Perspectives

“…Exhalative activity was responsible for the genesis of both tourmaline-bearing rocks and iron mineralisation. When metamorphosed, these protoliths produced tourmalinites and the metamorphic product of Algoma-type iron formation, both enriched with syngenetic gold mineralisation (Juliani 1993;Garda et al 2003Garda et al , 2005Garda et al , 2009Beljavskis et al 2003Beljavskis et al , 2005. Within this group, lowangle epigenetic shear zone-related gold mineralisation also occurs due to remobilisations of syngenetic gold (Martin et al 1998).…”