iron and taconite mining in mn supplying the nation for over 100 years
TRANSCRIPT
Iron and Taconite Mining in MN
Supplying the Nation For Over 100 Years
Iron Ore = Steel• Iron ore is main
ingredient in production of steel
• 98% of iron ore is used to manufacture steel
• MN produces about 80% of the nation’s iron ore
• Minnesota has led the nation in its production since the 1880s
Vermillion Iron Range
• Iron ore discovered by accident near Lake Vermillion in the 1860s
• Prospectors originally attracted to the area by a “gold rush” but little gold was found
• First shipment of iron ore occurred in 1884
Tower Sudan Mine
• At first ore was near the surface and easily mined• Over time, deposits were found deeper and required
expensive underground mines
Life as an Iron Miner• Mining was hard work• Early miners used
pickaxes and shovels• Horses and mules
hauled ore out of the mine
• Work was dangerous• Living conditions
often unhealthy• Bankruptcies were
common First mining camp near Mountain Iron in 1893
Mountain Iron Mine• Iron ore was discovered at
Mountain Iron on Mesabi Range a few years later
• First shipment occurred in 1892
• Most early mining done in underground mines but quickly switched to open pit because it was cheaper
• Steam shovels were able to do the work of many men
Mountain Iron Mine Now Closed – Ore Exhausted
Hull Rust Mine• World’s largest open pit
mine• Known as “Grand Canyon
of the North”• Over 3 miles long, a mile
wide and 535 feet deep • Material removed is equal
to digging a small tunnel from MN through the core of the earth and out the other side
• At its peak in 1940 this mine produced approximately 25% of US iron ore
Hibbing: The Town That Moved• Established in 1893 by German
miner Frank Hibbing who had discovered iron ore nearby
• In the 1920's the town moved two miles south to its present location after iron ore was discovered under the city's old location
• Buildings were moved using steel wheels and logs
• Move started in 1919 and took many years to complete
• More than 180 houses and 20 businesses were relocated to their current sites
Hill Annex Mine
• Iron mining began in 1913 and continued until 1978
• Was 6th largest mine in MN
MN’s Iron-Bearing Formations
Mesabi RangeVermillio
n Range
Cuyuna Range
Mesabi Range
• 97% of MN’s iron ore has come from the Mesabi Range
• Only small amounts have come from the Vermillion and Cuyuna Ranges
• Only active mines on the Mesabi
US Iron Production 1900-2000
Iron Ore Depletion
• By the 1970s most of MN’s high-grade iron ore was exhausted
• Production began to concentrate on a low-grade ore known as “taconite”
• Taconite consists of approximately 25-30% iron with the rest waste material
• Without processing, taconite cannot be used to produce steel
Taconite• Taconite is extremely
hard rock• Process begins with
blasting• Raw material then
transported to processing plant
Taconite Processing
• Taconite rock is first crushed
• Iron ore is separated by strong electronic magnets
• Formed into pellets
• Baked at high temperatures
Taconite Crusher
Taconite Separator
Taconite Pellets
• Finished taconite pellets transported to Duluth for shipment east
MN Taconite Plants
Butler Taconite
Hibbing Taconite
MinnTac
Major Arrowhead Urban Centers
Steel Production Centers