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USGS · 70019025

Feruvite from the Sullivan Pb-Zn-Ag deposit, British Columbia

S.-Y. Jiang·M. R. Palmer·A.M. McDonald·J. F. Slack·C.H.B. Leitch
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Abstract

Feruvite, an uncommon Ca- and Fe2+-rich tourmaline species, has been discovered in the footwall of the Sullivan Pb-Zn-Ag deposit (British Columbia) near gabbro sills and dikes. Its chemical composition varies according to occurrence: feruvite from the shallow footwall has lower Ca, higher Al, and higher X-site vacancies than that from the deep footwall. The major chemical substitution involved in the feruvite is the exchange vector CaMgO???-1Al-1(OH)-1. The most important factor controlling feruvite formation at Sullivan is likely the reaction of Fe-rich hydrothermal fluids with Ca-rich minerals in gabbro and host rocks. This reaction led to the breakdown of Ca-rich minerals (plagioclase and hornblende), with release of Ca to solution and its incorporation into feruvite. This process probably postdated the main stages of formation of fine-grained, intermediate schorl-dravite in the tourmalinite pipe in the footwall, and is attributed to postore intrusion of gabbro and associated albite-chlorite-pyrite alteration.

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S.-Y. Jiang, M. R. Palmer, A.M. McDonald, J. F. Slack, C.H.B. Leitch. 1996. Feruvite from the Sullivan Pb-Zn-Ag deposit, British Columbia. https://pubs.usgs.gov/publication/70019025

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