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jacobsite

noun
ja·​cobs·​ite | \ ˈjākəbˌzīt sometimes -kəpˌsīt\
plural -s

Definition of jacobsite

: a black magnetic isometric mineral MnFe2O4 consisting of an oxide of manganese and iron and constituting a member of the magnetite series

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History and Etymology for jacobsite

French jakobsite, from Jakobsberg, Sweden, its locality + French -ite

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