A peculiar dedolomitization phenomenon is associated with the supergene alteration of Zn-Pb sulfide ores, resulting in the precipitation of newly formed carbonate phases. In addition to the deposition of calcite and several metal carbonates, this phenomenon results in a widespread replacement of host-rock dolomites by zincian dolomite phases. In several studied districts Zn dolomite replaces the previous dolomite phases, and smithsonite may be high in Mg (to 15% MgO). The ample extent of the Zn dolomite replacement bodies, underestimated so far, is important for the exploration of nonsulfide Zn ores, because it may lead to an incorrect evaluation of the extractable metallic resources calculated from the assay data.
Zincian dolomite: A peculiar dedolomitization case? / Boni, Maria; Mondillo, Nicola; Balassone, Giuseppina. - In: GEOLOGY. - ISSN 0091-7613. - 39:2(2011), pp. 183-186. [10.1130/G31486.1]
Zincian dolomite: A peculiar dedolomitization case?
BONI, MARIA;MONDILLO, NICOLA;BALASSONE, GIUSEPPINA
2011
Abstract
A peculiar dedolomitization phenomenon is associated with the supergene alteration of Zn-Pb sulfide ores, resulting in the precipitation of newly formed carbonate phases. In addition to the deposition of calcite and several metal carbonates, this phenomenon results in a widespread replacement of host-rock dolomites by zincian dolomite phases. In several studied districts Zn dolomite replaces the previous dolomite phases, and smithsonite may be high in Mg (to 15% MgO). The ample extent of the Zn dolomite replacement bodies, underestimated so far, is important for the exploration of nonsulfide Zn ores, because it may lead to an incorrect evaluation of the extractable metallic resources calculated from the assay data.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
