ˈtant ə lˌīt noun
( -s )
Etymology: Swedish tantalit, from New Latin tantalum + Swedish -it -ite
: a mineral (FeMn)(TaCb) 2 O 6 consisting of a heavy iron-black oxide of iron, manganese, tantalum, and columbium that is isomorphous with columbite (hardness 6, specific gravity up to 7.3)