Abstract
The fluorspar deposits at Okorusu in north-central Namibia are spatially and genetically associated with the Okorusu early Cretaceous alkaline igneous-carbonatite complex. Fluorspar production at Okorusu has exceeded 130,000 tons of fluorspar concentrate per year, ranking Okorusu as one of the world’s great fluorspar-producing mines. Production has come from separate deposits at four open pits A–D.Geological study of the fluorspar ore deposits at the Okorusu mines indicate that 83% of the ores have formed by replacement of carbonatite, 16% by the replacement of marble of the intruded Precambrian Damara Series, and 1% by filling and replacement of fenite breccias.Fluorspar concentrates produced from fluorite ores that have replaced carbonatite typically are characterized by elevated amounts of phosphorus derived from replacement remnants of apatite from the replaced carbonatite. Concentrates from marble-replacement fluorite ores tend to contain elevated amounts of silica derived from quartz in the replaced marble.
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Hagni, R.D. (2012). The Replacement of Carbonatite and Marble by Fluorspar Ores and Its Relationship to Beneficiation Problems at Okorusu, Namibia. In: Broekmans, M. (eds) Proceedings of the 10th International Congress for Applied Mineralogy (ICAM). Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-27682-8_36
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DOI: https://doi.org/10.1007/978-3-642-27682-8_36
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