Usgs mineral Resources Program Niobium and Tantalum—Indispensable Twins

Yüklə 32,59 Kb.
Pdf görüntüsü
ölçüsü32,59 Kb.

USGS Mineral Resources Program

Niobium and Tantalum—Indispensable Twins

As part of a broad mission to 

conduct research and provide 

information on nonfuel mineral 

resources, the U.S. Geological 

Survey (USGS) supports science 

to understand

•  How and where niobium and 

tantalum resources form and 

concen trate in the Earth’s crust

•  How niobium and tantalum  

resources interact with the 

environment to affect human 

and ecosystem health

•  Trends in the supply of and 

demand for niobium and 

tantalum in the domestic and 

international markets

 Where undiscovered sources 

of  niobium and tantalum  

might be found

Why is this information important? 

Read on to learn about niobium 

and tantalum and the important 

role they play in the national 

economy, in national security, and 

in the lives of Americans every day. 

Niobium and tantalum are transition metals almost always paired together in nature. These “twins” 

are difficult to separate because of their shared physical and chemical properties. In 1801, English chemist 

Charles Hatchett uncovered an unknown element in a mineral sample of columbite; John Winthrop 

found the sample in a Massachusetts mine and sent it to the British Museum in London in 1734. 

The name columbium, which Hatchett named the new element, came from the poetic name for North 

America—Columbia—and was used interchangeably for niobium until 1949, when the name niobium 

became official. Swedish scientist Anders Ekberg discovered tantalum in 1802, but it was confused 

with niobium, because of their twinned properties, until 1864, when it was recognized as a separate 

element. Niobium is a lustrous, gray, ductile metal with a high melting point, relatively low density, and 

superconductor properties. Tantalum is a dark blue-gray, dense, ductile, very hard, and easily fabricated 

metal. It is highly conductive to heat and electricity and renowned for its resistance to acidic corrosion. 

These special properties determine their primary uses and make niobium and tantalum indispensable. 

How Do We Use Niobium and Tantalum?

The steel industry uses nearly 80 percent of the 

world’s produced niobium to manufacture high-

strength low-alloy steels. Niobium, a grain refiner 

and precipitation hardener, enhances the steels’ 

mechanical strength, toughness, high-temperature 

strength, and corrosion resistance for use in 

pipelines, transportation, and structural applications. 

Appreciable amounts (>20 percent) of niobium are 

used in nickel-, cobalt-, and iron-based superalloys 

for high-temperature applications in jet engines, 

gas turbines, rocket subassemblies, turbocharger 

systems, and combustion equipment. Niobium  

alloys are used to manufacture superconducting 

magnets for medical hardware such as magnetic 

resonance imaging (MRI) and nuclear magnetic 

resonance (NMR) instruments. A new use of 

niobium is in a solid niobic acid that catalyzes the 

conversion of palm oil to bio-diesel fuel. Niobium’s uses are specialized; substituting an alternative  

can lead to reduced performance and increased cost.

Tantalum has a unique ability to store and release energy, which is why the electronics industry  

consumes more than one-half of tantalum production. Tantalum-based components can be exceptionally  

small, and other elements cannot serve as substitutes without degrading the performance of electronic 

devices. As a result, tantalum is used in components for items as ubiquitous as cell phones, hearing aids, 

and hard drives. Tantalum’s low mechanical strength and high biocompatibility allow it to coat stronger 

substrates, like stainless steel, for medical applications. It is used for blood vessel support stents, plates, 

bone replacements, and suture clips and wire. In the chemical industry, tantalum’s corrosion resistance makes 

it useful as a lining for pipes, tanks, and vessels. Tantalum oxide can increase the refractive index of lens glass, 

while the hardness of tantalum carbide makes it an ideal component in the manufacture of cutting tools.

Where Do Niobium and Tantalum Come From?

The average abundance of niobium and tantalum in bulk continental crust is low, with 8.0 parts per 

million (ppm) niobium and 0.7 ppm tantalum. Their chemical characteristics reduce their potential to 

substitute for more common elements in rock-forming minerals and make them practically immobile in 

many aqueous solutions. Niobium and tantalum do not occur naturally as pure metals, but are concentrated 

in rare oxide and hydroxide minerals and in a few rare silicate minerals. The economically important ore 

minerals for niobium and tantalum production are all oxides. Niobium is primarily derived from the complex 

oxide minerals of the pyrochlore group ((Na,Ca,Ce)






), which are found in some 

alkaline (igneous rocks containing certain sodium- or potassium-rich minerals) granite-syenite and carbon-

atite complexes (igneous rocks composed more than 50 percent by volume of primary carbonate minerals). 

Tantalum is derived mainly from the mineral tantalite ((Fe,Mn)(Ta,Nb)




), which is found as an accessory 

mineral in rare-metal granites and pegmatites enriched in lithium and cesium (termed the LCT family).

Launch of the Gemini 12 space 

mission (image courtesy of NASA). 

Thousands of pounds of niobium 

have been used in advanced air 

frame systems such as were used 

in the Gemini space program.

















Central view of the ATLAS detector in the Large Hadron 

Collider with its eight superconducting magnets (toroids) 

around the calorimeter (note person standing in lower 

center of photograph for scale). This is the world’s 

largest superconducting magnet. (Image from European 

Council for Nuclear Research [CERN]).

U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2014 –3054 

June 2014


Did you know...


Niobium alloys are contained in the superconducting magnets used in particle accelerators 








Did you know...


Niobium is widely used for body piercing, and when put through an anodizing process results 

              in varying colors of jewelry without the use of toxic inks or dyes.

The Future of Niobium and Tantalum: Worldwide Supply and Demand 

Estimated global reserves and resources of niobium and tantalum are large and more 

than sufficient to meet global demand for the foreseeable future, possibly the next 500 years. 

Therefore, geologic availability does not appear to be a major concern for the supply 

of niobium or tantalum. Brazil, Canada, and Australia are the leading global producers 

of niobium and tantalum mineral concentrates. Brazil produces the greatest amount of 

niobium mineral concentrates (~90 percent), while Australia and Brazil together lead in 

the production of tantalum mineral concentrates. A number of African countries—Burundi, 

Democratic Republic of Congo, Ethiopia, Mozambique, Nigeria, Rwanda, Uganda—mine 

for tantalum minerals (such as columbite-tantalite, also called coltan) through artisanal 

mining or are establishing mining operations. Primary production of niobium or tantalum in 

the United States has not been reported since the late 1950’s;  therefore, the United States 

has to meet its current and expected future needs by importing primary mineral concentrates 

and alloys, and by recovering them from foreign and domestic alloy scrap.

Fluctuating market conditions, as with the recent worldwide economic 

crises, interrupted operations at a number of production sites, and future 

economic instability has the potential to generate supply problems. Other 

possible disruptions include war, civil unrest, political changes, natural 

disasters, environmental issues and market manipulation. For example, rebel 

sales of “conflict coltan” in the Democratic Republic of Congo, amidst a civil 

war, have led to discussions about supply-line transparency and traceability as 

tools for excluding illegal columbite-tantalite while keeping the market open 

for legitimate, small-scale artisanal mining in central Africa.

To help predict where future niobium and tantalum supplies might be 

found, USGS scientists study how and where these resources are concentrated 

in the Earth’s crust and then assess the likelihood that undiscovered resources 

may exist. Techniques to assess mineral resource potential have been 

developed by the USGS to support the stewardship of Federal lands and 

better evaluate mineral resource availability in a global context. The USGS 

also compiles statistics and information on the worldwide supply, demand, 

and flow of niobium and tantalum. These data help support the U.S. economy 

and national security.

ISSN 2327– 6932 (online)

The USGS Mineral Resources Program is the principal 

Federal provider of research and information on niobium, 

tantalum, and other nonfuel mineral resources.

For more information, please contact:

Mineral Resources Program Coordinator

U.S. Geological Survey

913 National Center

Reston, VA 20192

Telephone: 703–648–6100

Fax: 703–648–6057


Home page:

For More Information

•  On production and consumption of niobium and tantalum:

•  On historical statistics on niobium and tantalum:

•  On recycling of niobium and tantalum in the United States:

Any use of trade, firm, or product names is for descriptive purposes 

only and does not imply endorsement by the U.S. Government.

Capacitor from Fotosearch Stock Images at

















Text prepared by Klaus Schulz and John Papp.

High-purity niobium crystals, electrolytic made, as well 

as a high-purity 1 cubic centimeter anodized niobium 

cube for comparison (photograph from Wikipedia).

The large Mibra (Volta Grande) open-pit pegmatite mine operated 

by Companhia Industrial Fluminense’s in Brazil (Itamar Resende). 

(Image from Tantalum-Niobium International Study Center).

Document Outline

  • How Do We Use Niobium and Tantalum?
  • Where Do Niobium and Tantalum Come From?
  • The Future of Niobium and Tantalum: Worldwide Supply and Demand
  • For More Information 

Yüklə 32,59 Kb.

Dostları ilə paylaş:

Verilənlər bazası müəlliflik hüququ ilə müdafiə olunur © 2024
rəhbərliyinə müraciət

    Ana səhifə