Also found in: Dictionary, Thesaurus, Wikipedia.


low-grade iron ore, a flintlike rock usually containing less than 30% iron. Resistant to drilling and to the extraction of its contained metal, the rock was long considered worthless. Experiments begun in 1912 by the American scientist Edward W. Davis and continued by him for nearly 40 years produced the pelletizing method for upgrading the ore. The development of the jet piercer (a high-temperature flame thrower) provided penetration speeds of up to 40 ft (12 m) an hour for blasting holes in the rock. In 1956 exploitation of the vast reserves of taconite in the Mesabi range of Minnesota was begun by some of the largest steel companies in the United States.



metamorphosed, stratified, ferruginous rock of Precambrian age consisting of metalliferous and nonmetalliferous quartzites and schists alternating with and passing into one another many times. Taconite’s composition may include quartz, hematite, magnetite, biotite, chlorites, amphiboles, and carbonates. In the USSR, Precambrian ferruginous rocks, including ta-conite, are usually referred to as ferruginous quartzites. Taconites, especially magnetite forms, are mined as iron ores, for example, in the Labrador Iron Ore Belt.


The siliceous iron formation from which high-grade iron ores of the Lake Superior district have been derived; consists chiefly of fine-grained silica mixed with magnetite and hematite.
References in periodicals archive ?
The cash cost of goods expectation includes $9 million per month of idle costs for the Northshore and United Taconite mines.
Outspoken Cliffs CEO Lourenco Goncalves has been openly critical of the Essar project, telling Minnesota media oudets that Nashwauk will harm his company's operations and produce a glut of taconite on the market.
The revision was wrought by Gogebic Taconite, which lobbied state legislators for years in order to get them to water down the longstanding mining law.
We supply firm power to five taconite producers, and we are working ever more closely with them to ensure their survival in the face of complex domestic and global economic forces.
We believe re-fueling Laskin and retiring one generating unit at our Taconite Harbor facility are the most cost effective solutions for our small coal units to comply with state and federal regulations," said Minnesota Power Vice President of Strategy and Planning Al Rudeck.
An initial mineral resource estimation will also be provided on the Elizabeth Lake Taconite.
MSHA cited both United Taconite and the manager for violations under [section]56.
The taconite mine extension project received the necessary state permits earlier this year.
drill test taconite targets identified in 2011: an initial diamond drill programme (2,400 m) will target taconite iron mineralization in both Quebec and Labrador.
Essar Steel Minnesota has signed a long-term agreement to purchase the electricity it needs to operate a taconite mine, processing plant, and later a steel mill, from the city of Nashwauk, Minn.
The highway must be moved to allow United Taconite access to expand its taconite iron ore pit under the current roadway.
This taconite plant currently produces 15 million tons of ore for use in steel mills.