TY - JOUR
T1 - Systematic and integrative ore characterization of massive sulfide deposits
T2 - An Example from voisey's bay Ni-Cu-Co Ovoid Orebody, Labrador, Canada
AU - Huminicki, M. A.E.
AU - Sylvester, P. J.
AU - Shaffer, M.
AU - Wilton, D. H.C.
AU - Evans-Lamswood, D.
AU - Wheeler, R. I.
PY - 2012/1
Y1 - 2012/1
N2 - Systematic characterization of the mineralogy of massive sulfide ore deposits can provide valuable insights into ore genesis and metallurgical processing that would not be apparent otherwise. We describe a method wherein (1) normative mineral abundances are calculated from whole-rock chemical assays using an algorithm, (2) the results are cast in block models, (3) the results are then verified with automated image analysis of a subset of samples prepared as grain mounts by backscattered electron imaging and X-ray mapping on a scanning electron microscope, and (4) those verified results are integrated with textural data determined by optical microscopy. The technique is applied to the magmatic Ni-Cu-Co sulfides of the Ovoid orebody, based on geochemical assays of 3175 whole-rock samples. Three principal ore zones are defined in the Ovoid. Type I ore occurs in the center of the deposit; it is magnetite-rich and pyrrhotite-poor with intermediate contents of pentlandite and chalcopyrite. Type II ore surrounds Type I ore and is pentlanditechalcopyrite-rich with intermediate contents of pyrrhotite and magnetite. Type III ore occurs at the base and along the outer periphery of the northern part of the orebody; it is pyrrhotite-rich and chalcopyrite-poor with an intermediate content of pentlandite, and a low-to-intermediate content of mag netite.
AB - Systematic characterization of the mineralogy of massive sulfide ore deposits can provide valuable insights into ore genesis and metallurgical processing that would not be apparent otherwise. We describe a method wherein (1) normative mineral abundances are calculated from whole-rock chemical assays using an algorithm, (2) the results are cast in block models, (3) the results are then verified with automated image analysis of a subset of samples prepared as grain mounts by backscattered electron imaging and X-ray mapping on a scanning electron microscope, and (4) those verified results are integrated with textural data determined by optical microscopy. The technique is applied to the magmatic Ni-Cu-Co sulfides of the Ovoid orebody, based on geochemical assays of 3175 whole-rock samples. Three principal ore zones are defined in the Ovoid. Type I ore occurs in the center of the deposit; it is magnetite-rich and pyrrhotite-poor with intermediate contents of pentlandite and chalcopyrite. Type II ore surrounds Type I ore and is pentlanditechalcopyrite-rich with intermediate contents of pyrrhotite and magnetite. Type III ore occurs at the base and along the outer periphery of the northern part of the orebody; it is pyrrhotite-rich and chalcopyrite-poor with an intermediate content of pentlandite, and a low-to-intermediate content of mag netite.
KW - Massive sulfide deposits
KW - Mineral liberation analyzer
KW - Quantitative mineralogy
KW - Voisey's Bay Ovoid orebody
UR - http://www.scopus.com/inward/record.url?scp=84877148472&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:84877148472
SN - 0964-1823
VL - 20
SP - 53
EP - 86
JO - Exploration and Mining Geology
JF - Exploration and Mining Geology
IS - 1
ER -