iron and taconite mining in mn supplying the nation for over 100 years

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