@misc{10481/93523,
year = {2024},
month = {6},
url = {https://hdl.handle.net/10481/93523},
abstract = {This paper provides a top-down nanoscale analysis of Cu-Ni-Fe sulfide inclusions in laurite from the Taitao ophiolite (Chile) and the Kevitsa mafic-ultramafic igneous intrusion (Finland). High-resolution transmission electron microscopy (HRTEM) reveal that Cu-Ni-Fe sulfide inclusions are euhedral to (sub)-anhedral (i.e., droplet-like) and form single, biphasic or polyphasic grains, made up of different polymorphs, polytypes and polysomes even within a single sulfide crystal. Tetragonal (I4d) and cubic (F3m) chalcopyrite (CuFeS2) host frequent fringes of bornite (Cu5FeS4; cubic F3m and/or orthorhombic Pbca) ± talnakhite (Cu9(Fe, Ni)8S16; cubic I3m) ± pyrrhotite (Fe1 − xS; monoclinic C2/c polytype 4C and orthorhombic Cmca polytype 11C) ± pentlandite ((Ni, Fe)9S8; cubic Fm3m). Pentlandite hosts fringes of pyrrhotite, bornite and/or talnakhite. Laurite and Cu-Fe-Ni sulfide inclusions display coherent, semi-coherent and incoherent crystallographic orientation relationships (COR), defined by perfect edge-to-edge matching, as well as slight (2–4º) to significant (45º) lattice misfit. These COR suggest diverse mechanisms of crystal growth of Cu-Fe-Ni sulfide melt mechanically trapped by growing laurite. Meanwhile, the mutual COR within the sulfide inclusions discloses: (1) Fe-Ni-S melt solidified into MSS re-equilibrated after cooling into pyrrhotite ± pentlandite, (2) Cu-Ni-Fe-S melts crystallized into the quaternary solid solution spanning the compositional range between heazlewoodite [(Ni, Fe)3±xS2] (Hzss) and ISS [(Cu1±x, Fe1±y)S2]. Additionally, nanocrystallites (50–100 nm) of Pt-S and iridarsenite (IrAsS) accompanying the sulfide inclusions spotlight the segregation of PGE-rich sulfide and arsenide melt earlier and/or contemporarily to laurite crystallization from the silicate magmas. Cobaltite (CoAsS)-gersdorffite (NiAsS) epitaxially overgrown on laurite further supports the segregation of arsenide melts at early stages of chromitite formation.},
organization = {Spanish Grant
NANOMET PID2022-138768OB-I00 funded by MCIN/AEI/https://
doi.org/10.13039/50110001133},
organization = {“ERDF A way of making
Europe” by the “European Union”},
organization = {PRE2019-088262
“Ayudas para contratos predoctorales para la formación de doctores”
(FPI), defrayed by the “Ministerio de Ciencia, Innovación y Universidades},
organization = {Chilean National Research and Development Agency
(ANID) through the FONDECYT Project 1211820},
publisher = {Springer},
keywords = {Nanoscience},
keywords = {Mineralogy},
keywords = {Sulfide},
title = {Micron-to-nanoscale investigation of Cu-Fe-Ni sulfide inclusions within laurite (Ru, Os)S2 from chromitites},
doi = {10.1007/s00126-024-01285-0},
author = {González Jiménez, José María and González Pérez, Igor and Plissart, Gaëlle and Ferreira, Amira R. and Schettino, Erwin and Yesares, Lola and Schilling, Manuel E. and Corgne, Alexandre and Gervilla Linares, Fernando},
}