Tantalum

Symbol: Ta
Category: Transition metal
Atomic number:  73
Atomic weight: 180.947

Physical Properties:

State:  solid
Melting Point: 3293 K (3020˚C)
Boiling Point: 5833 K (5560˚C)

Energy Properties:

Specific heat capacity: 0.14 J g-1K-1 Heat of fusion: 36.57 kJ mol-1
Heat of atomization:  782 kJ mol-1 Heat of vaporization: 737 kJ mol-1
1st ionization energy: 761 kJ mol-1 2nd ionization energy: 1500 kJ mol-1
Electron affinity: 31.1kJ mol-1

Atomic properties:

Oxidation states: 5,4,3,2,-1 (mildly acidic oxide) Electronegativity: 1.5 Pauling Scale
Atomic radius: 146 pm Covalent radius: 170±8 pm

What is Tantalum?

Tantalum is a hard, shiny blue-gray, ductile metal. It is highly conductive and can be drawn into a thin wire. Tantalum was discovered in Sweden in 1802 by Anders Ekeberg and named after the Grecian hero Tantalus. Tantalum displays a high resistance to corrosion by acids and at temperatures below 150˚C, can be completely immune to the highly corrosive aqua regia. Tantalum is only susceptible to hydrofluoric acid, acidic fluoride ions and free sulphur trioxide. Its melting point is exceeded only by tungsten, rhenium, osmium and carbon.  Extraction of tantalum is achieved in commercially viable quantities through the formation of tantalum pentoxide (Ta2O5).

What is tantalum used for?

Tantalum is an important metal in the electronics industry. It is an excellent conductor and is used to make capacitors and high power resistors for electronic. Due to their size and weight, tantalum capacitors are of prime importance in portable and automotive electronics. Tantalum is also an integral component for use in alloys to increase strength, ductility and corrosion resistance. Tantalum can also be paired with other metals to create carbides that are essential for tools and superalloys that can be used in jet engine components, nuclear reactors, missile parts and chemical process equipment. It is also found in surgical tools and implants. The metal is also used in high refractive index glass in camera lenses.

Where is tantalum found?

Tantalum is not found free in nature, but in minerals such as columbite and tantalite. Typically, niobium can also be found in minerals that contain tantalum. Mining for tantalum is in Western Australia and Brazil. Other significant sources of mineral are Canada, central Africa as well as China and Southeast Asia. Tantalum can also be found as a byproduct of tin.

Several countries are also undergoing exploration for tantalum in hopes to be future producers: United States, Finland, Greenland, Egypt and Saudi Arabia.

Conflict minerals?

Countries in Central Africa, such as the Democratic Republic of the Congo, Rwanda and the surrounding nations have previously been producers of significant quantities of tantalum and other minerals. However, with increased political instability, and the funding of militias through the exploitation of minerals and natural resources, organizations such as the Tantalum-Niobium International Study Center, The Enough Project, among others are urging end users and manufacturers to find sources of certified, conflict-free minerals such as tantalum.

Tantalum Producers

Australia’s Global Advanced Metals currently produces between 25% and 35% of the world’s tantalum. The company operates two mines in Western Australia, Greenbushes and Wodgina.

The largest tantalum mine in operation is the Advanced Materials Group’s Mibra mine in Brazil. The mine has the capacity to produce 300,000 lb Ta2O5 per year, the equivalent of 20% of global production.

Noventa (AIM:NVTA) reopened the Marropino mine tantalum in Mozambique in April of 2010. In 2008, Marropino was the second largest tantalum mine in operation with the production of 200-300,000 lb of Ta2O5.

Future producers of tantalum?

Several junior mining companies are actively exploring for tantalum in Canada, and Saudi Arabia.

Avalon Rare Metals (TSE:AVL) is a Canadian mineral exploration company with a focus on rare metals and minerals. The company’s Separation Rapids project in Northwestern Ontario is a tantalum bearing granitic pegmatite property that also holds lithium, cesium and rubidium. Tantalum is also found in heavy rare earth element bearing mineral fergusonite at the company’s Thor Lake project in the North West Territories.

Commerce Resources (CVE:CCE) is an exploration and development company with a particular focus on deposits of rare metals and rare earth elements.  The company is specifically focused on the development of its Upper Fir Tantalum and Niobium Deposit at the Blue River Project in British Columbia.

Critical Elements Corp. (CVE:CRE) is a Laval, Quebec-based mineral exploration company focused on rare metal, gold and silver production. Critical Elements Corp. recently announced the results of 65 drill holes on the Lac Pivert / Rose property, reporting significant mineral findings of lithium, tantalum, rubidium, cesium, gallium and beryllium.

Gippsland Limited (ASX:GIP) is an Australian based international resource company. Their focus is to find projects that have had detailed historical analysis, which may have been overlooked by major resource groups. Currently, their main projects are the Abu Dabbab and the Nuweibi tantalum projects, located in Egypt.  The Abu Dabbab has earned the JORC (Joint Ore Reserves Committee) Code compliant Resource and Reserve base to sustain long-term, low-cost, non-conflict tantalum production for several decades.