165109 20251212165958.0 doi 10.1016/j.jafrearsci.2025.105915 sideral 146644 ART-2025-146644 eng Hajjar, Zaineb An overview of the Co-Ni-Fe arsenide ore zoning in the Bou Azzer mining district (Central Anti-Atlas, Morocco) 2025 Co-Ni-Fe-bearing arsenide ores in the Bou Azzer district (Anti-Atlas, Morocco) occur alongside serpentinite and are mainly found as contact-type ores or serpentinite-hosted ores. There is a clear zoning pattern in the contact-type ores, evolving from Ni-Co ores and Co-Ni ores filling fault-related open spaces at the serpentinite contact to Fe-Co types within the serpentinite itself. This trend is supported by drill core geochemistry. In serpentinite-hosted orebodies, the arsenide minerals are primarily Fe-Co ores, which preserve cores of Co-Fe ores. Our key contribution is to identify the chemical evolution of the ore-forming fluid. Co and Fe enrichment facilitated the progressive transition from Ni-Co to Co-Fe ores, while subsequent Ni depletion and Fe enrichment generated the disseminated Co-Fe ores (i.e., contact-type ores). Further circulation of these ore-forming fluids through intra-serpentinite weak fault zones tends to precipitate Fe-Co ores surrounding Co-Fe ores (i.e., serpentinite-hosted ores). Critically, we show that the established west-to-east district zoning (decreasing Co, increasing Ni) is specific to contact-type ores and may be influenced by the composition of the adjacent country rock (high Ni content is related to mafic layer in the contact. Serpentinite-hosted ores in the Ait Ahmane area appear to follow this west-east zoning process. info:eu-repo/grantAgreement/ES/MCIU/RTI2018-099157-A-I00 info:eu-repo/grantAgreement/ES/MINECO/RYC-2015-17596 info:eu-repo/semantics/closedAccess All rights reserved http://www.europeana.eu/rights/rr-f/ info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Fanlo, Isabel Universidad de Zaragoza (orcid)0000-0002-0302-2737 Ilmen, Said Bendaoud, Rachida Gervilla, Fernando 2000 120 Universidad de Zaragoza Dpto. Ciencias de la Tierra Área Cristalografía Mineralog. 234 (2025), 105915 [16 pp.] J. Afr. earth sci. Journal of African Earth Sciences 1464-343X 9746730 http://zaguan.unizar.es/record/165109/files/texto_completo.pdf Versión publicada 2567114 http://zaguan.unizar.es/record/165109/files/texto_completo.jpg?subformat=icon icon Versión publicada oai:zaguan.unizar.es:165109 articulos driver 2025-12-12-14:42:51 ARTICLE