Mineral Resource of the Month: Chromium

PRODUCTION

Chromite seams (dark layers) located in the Bushveld Complex, South Africa. Credit: courtesy Klaus Schultz, USGS. Chromite seams (dark layers) located in the Bushveld Complex, South Africa. Credit: courtesy Klaus Schultz, USGS

GEOLOGIC OCCURENCE

Although chromium is a metal, it does not occur naturally in metallic form. Chromium can be found in many minerals, but the only economically significant chromium-bearing mineral is chromite. Chromite has been mined from four different deposit types: stratiform chromite, podiform chromite, placer chromite, and laterite deposits. Most of the world’s resources, however, are located in stratiform chromite deposits, such as the Bushveld Complex in South Africa. The economic potential of chromite resources depends on the thickness and continuity of the deposit and on the grade of the ore. Many of the major stratiform chromite deposits also contain economic levels of platinum, palladium, rhodium, osmium, iridium and ruthenium.


GLOBAL PRODUCTION OF CHROMITE ORE (CHROMIUM CONTENT), 1900-2016

 K. Cantner, AGI. K. Cantner, AGI


GLOBAL PRODUCTION OF CHROMITE ORE BY COUNTRY IN 2016 (CHROMIUM CONTENT)

 K. Cantner, AGI. K. Cantner, AGI

 

CONSUMPTION

U.S. APPARENT CONSUMPTION OF CHROMITE ORE, FERROCHROMIUM, FERROSILICON CHROMIUM AND STAINLESS STEEL (CHROMIUM CONTENT)

 K. Cantner, AGI. K. Cantner, AGI


U.S. IMPORT SOURCES OF CHROMITE ORE, FERROCHROMIUM, FERROSILICON CHROMIUM AND STAINLESS STEEL IN 2016 (CHROMIUM CONTENT)

 K. Cantner, AGI. K. Cantner, AGI

 


Stainless steel tube flange used in water piping. Credit: public domain.Stainless steel tube flange used in water piping. Credit: public domain

COMMERCIAL USAGE

The major markets for chromium materials are chromium chemicals, ferroalloys and metal. The primary uses of chromium are in stainless steels, nonferrous alloys and chromium plating. Chromite ore can also be roasted to make sodium dichromate, which is subsequently converted to chromium chemicals used in pigments and metal coatings. Chromium is also an important component in refractories, foundry applications, and as a nutrient.

FUN FACTS

  • The word “chromium” is derived from the Greek word “chroma,” which means color, because many chromium compounds are colorful. Without chromium, emeralds would not be green and rubies would not be red.

  • Trivalent chromium (Cr(III)) is an important micronutrient and improves the efficiency of insulin in individuals with impaired glucose tolerance. Meats, vegetables, fruits and grains are metabolic sources of chromium.

 

Visit minerals.usgs.gov/minerals for more information

design by K. Cantner and N. Schmidgall, AGI

Credit: United States Geological Survey. Credit: U.S. Geological Survey

Credit: The American Geosciences Institute. Credit: American Geosciences Institute

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Wednesday, June 13, 2018 - 06:00

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