@article{fdi:010061488,
  title = {{XAS} evidence for {N}i sequestration by siderite in a lateritic {N}i-deposit from {N}ew {C}aledonia},
  author = {{D}ublet, {G}. and {J}uillot, {F}arid and {M}orin, {G}. and {F}ritsch, {E}mmanuel and {N}oel, {V}. and {B}rest, {J}. and {B}rown, {G}. {E}.},
  editor = {},
  language = {{ENG}},
  abstract = {{M}ineralogical and spectroscopic analyses were conducted on a lateritic {N}i-deposit from {S}outhern {N}ew {C}aledonia. {R}esults show that {N}i is incorporated in siderite ({F}e{CO}3) found between 37 and 40 m depth in the laterite and saprolite units of the regolith. {SEM}-{EDXS} analyses of siderite-rich samples indicate that a significant amount of nickel can be hosted by this crystalline phase (similar to 0.8 wt% {N}i{O}). {N}i and {F}e {K}-edge extended {X}-ray absorption fine structure ({EXAFS}) spectroscopic analyses of the siderite-rich samples from the regolith as well as comparison with synthetic {N}i-bearing and {N}i-free siderites demonstrate isomorphous substitution of {N}i2+ for {F}e2+ in the siderite structure. {L}inear combination fitting ({LCF}) of the {N}i {K}-edge {EXAFS} data reveals that this {N}i-bearing siderite species accounts for more than 90% of the total {N}i pool (1 wt% {N}i{O}) in the siderite-rich horizons of the regolith. {I}n addition, {LCF} analysis of the {EXAFS} spectra indicates that goethite and serpentine are the major {N}i hosts in the upper horizons (laterite) and lower horizons (saprolite) of the regolith, respectively. {F}ormation of siderite, an uncommon mineral species in such oxidized environments, is attributed to the development of swampy conditions in organic-rich lateritic materials that accumulated at the bottom of dolines. {T}hese results thus show the importance of siderite as a host for nickel in lateritic {N}i deposits that have been affected by late hydromorphic and reducing conditions.},
  keywords = {{S}iderite ; {XAS} ; nickel ; laterite ; speciation ; {NOUVELLE} {CALEDONIE}},
  booktitle = {},
  journal = {{A}merican {M}ineralogist},
  volume = {99},
  numero = {1},
  pages = {225--234},
  ISSN = {0003-004{X}},
  year = {2014},
  DOI = {10.2138/am.2014.4625},
  URL = {https://www.documentation.ird.fr/hor/fdi:010061488},
}