Mesabi (məsäbˈē) [key], range of low hills, NE Minn., once
famous for its extensive iron ore deposits. The ores were found
in a belt c.110 mi (180 km) long and from 1 to 3 mi (1.6–4.8 km)
wide between Babbitt and Grand Rapids, occurring in horizontal
layers (up to 500 ft/152 m thick) near the surface and mined by
the open pit method. Reserves of high-grade hematite iron are
now exhausted, and lower-grade taconite deposits are being
worked. The taconite contains mostly chert and magnetite (an
iron-bearing mineral) and must undergo a costly and complex
beneficiation process before being shipped in the form of
pellets containing c.60% iron. Most of the ore found is shipped
by rail to Duluth, Minn., and other ports on Lake Superior. The
Mesabi iron ore deposits were first discovered in 1887 by
Leonidas Merritt and his brothers, who organized the Mountain
Iron Company in 1890 to mine the ore; John D. Rockefeller gained
control of the company in the Panic of 1893. The Columbia
Electronic Encyclopedia, 6th ed. Copyr