Indexat a

Llicència i ús

Citacions

Cited 1 times in

Cited 1 times in

Altmetrics

Grant support

The elaboration of this work has benefited from the valuable collaboration of numerous individuals and institutions. This paper was written during the Visiting Scientist stay of Mario Iglesias-Martinez at CSIRO Mineral Resources, funded by the Spanish Scholarship program " Ayuda para la Recualificacion del Sistema Universitario Espanol (Margarita Salas) " through the Universidad Politecnica de Madrid , as part of the European Union funds Next Generation EU. Special thanks are due to Walid Salama and Ryan Noble, who supported Mario's stay at CSIRO Mineral Resources. Thanks to Belinda Godell for the micro-CT images and Raymond E. Smith, Yoram Teitler, Ian Tyler and Daniel Mueller for revising the manuscript.

Anàlisi d'autories institucional

Compartir

Exploration and mining of lateritic gold deposits (Part I): Ore formation, characterization, and sampling of ferruginous gravel and duricrust

Publicat a:Ore Geology Reviews. 170 106146- - 2024-07-01 170(), DOI: 10.1016/j.oregeorev.2024.106146

Autors: Iglesias-Martínez, M; Salama, W; Anand, RR; Butt, CRM; Espí, JA

Afiliacions

Resum

Lateritic gold deposits are emerging as a substantial reservoir of precious metals. The growing demand and escalating gold price have focused on lateritic gold and other supergene deposits due to their potential for lowcost production. The occurrence of gold in economic concentrations has been described in supergene-enriched mineralization in many regions dominated by intensely weathered terrains of the humid tropics and subtropics, such as equatorial rainforests, savannas, and some Mediterranean regions. Lateritic gold deposits also occur in semi-arid belts with historically similar climates. These deposits form through the physical accumulation and biological and chemical redistribution of Au during the weathering of primary mineralization. This study focuses on the upper ferruginous part of a lateritic profile known as Ferruginous Gravels and Duricrust (FGD) deposits, which includes lateritic residuum and/or similar ferricrete, overlying the ferruginous saprolite or mottled zone. The FGD and saprolite are separate systems with different physical and chemical conditions for Au mobilization. Intense artisanal mining in areas considered barren by geochemical surveys reveals disparities in sampling and analytical methods, such as panning for coarse gold versus geochemical analysis of fine fractions. Coarse gold in FGD significantly contributes to total gold content. Still, small drill samples fail to represent gold distribution accurately-the friable nature of lateritic materials results in low sample recovery rates (55%-70%). This paper synthesizes information from diverse deposits in Africa, South America, and Australia, drawing on academic papers and technical reports from industry to provide a comprehensive global overview of the supergene gold metallogeny and exploration strategies leading to enhance the success of new discoveries or the reassessment of known deposits.

Paraules clau