TY - JOUR
T1 - Geological, geochemical and mineralogical characteristics of REE-bearing Las Mercedes bauxite deposit, Dominican Republic
AU - Torró, L.
AU - Proenza, J. A.
AU - Aiglsperger, T.
AU - Bover-Arnal, T.
AU - Villanova-de-Benavent, C.
AU - Rodríguez-García, D.
AU - Ramírez, A.
AU - Rodríguez, J.
AU - Mosquea, L. A.
AU - Salas, R.
PY - 2017/6/13
Y1 - 2017/6/13
N2 - Bauxite deposits, traditionally the main source of aluminum, have been recently targeted for their remarkable contents in rare earth elements (REE). With ∑REE (lanthanoids + Sc + Y) concentrations systematically higher than ∼1400 ppm (av. = 1530 ppm), the Las Mercedes karstic bauxites in the Dominican Republic rank as one of the REE-richest deposits of its style. The bauxitic ore in the Las Mercedes deposit is mostly unlithified and has a homogeneous-massive lithostructure, with only local cross-stratification and graded bedding. The dominant arenaceous and round-grained texture is composed of bauxite particles and subordinate ooids, pisoids and carbonate clasts. Mineralogically, the bauxite ore is composed mostly of gibbsite and lesser amounts of kaolinite, hematite, boehmite, anatase, goethite, chromian spinel and zircon. Identified REE-minerals include cerianite and monazite-Ce, whose composition accounts for the steady enrichment in light- relative to medium- and heavy-REE of the studied bauxites. Considering the paleo-geomorphology of the study area, we propose that bauxites in the Las Mercedes deposit are the product of the erosion and deposition of lithified bauxites located at higher elevations in the Bahoruco ranges. Based on the available data, we suggest a mixed lithological source for the bauxite deposits at the district scale: bedrock carbonates and an igneous source of likely mafic composition.
AB - Bauxite deposits, traditionally the main source of aluminum, have been recently targeted for their remarkable contents in rare earth elements (REE). With ∑REE (lanthanoids + Sc + Y) concentrations systematically higher than ∼1400 ppm (av. = 1530 ppm), the Las Mercedes karstic bauxites in the Dominican Republic rank as one of the REE-richest deposits of its style. The bauxitic ore in the Las Mercedes deposit is mostly unlithified and has a homogeneous-massive lithostructure, with only local cross-stratification and graded bedding. The dominant arenaceous and round-grained texture is composed of bauxite particles and subordinate ooids, pisoids and carbonate clasts. Mineralogically, the bauxite ore is composed mostly of gibbsite and lesser amounts of kaolinite, hematite, boehmite, anatase, goethite, chromian spinel and zircon. Identified REE-minerals include cerianite and monazite-Ce, whose composition accounts for the steady enrichment in light- relative to medium- and heavy-REE of the studied bauxites. Considering the paleo-geomorphology of the study area, we propose that bauxites in the Las Mercedes deposit are the product of the erosion and deposition of lithified bauxites located at higher elevations in the Bahoruco ranges. Based on the available data, we suggest a mixed lithological source for the bauxite deposits at the district scale: bedrock carbonates and an igneous source of likely mafic composition.
KW - Dominican Republic
KW - High tech metals
KW - Karstic bauxite
KW - REE
UR - http://www.scopus.com/inward/record.url?scp=85033382059&partnerID=8YFLogxK
U2 - 10.1016/j.oregeorev.2017.06.017
DO - 10.1016/j.oregeorev.2017.06.017
M3 - Article
AN - SCOPUS:85033382059
SN - 0169-1368
VL - 89
SP - 114
EP - 131
JO - Ore Geology Reviews
JF - Ore Geology Reviews
ER -