taconite

/ˈtækənaɪt/
noun
  1. A low-grade iron ore found in the United States, especially in Minnesota and Michigan, that is processed to extract iron.
    • Many towns in northern Minnesota rely on taconite mining for jobs.
    • Taconite is crushed and processed into pellets for steelmaking.
    • The mining company extracts taconite from the Mesabi Range.