Tamil Nadu's Resolution against Tungsten (or Wolfram) Mining

Tamil Nadu’s Resolution against Tungsten (or Wolfram) Mining

The Tamil Nadu Legislative Assembly unanimously adopted a special resolution urging the Union government to immediately cancel the tungsten mining rights granted to Hindustan Zinc Limited in Madurai district.

Table of Contents

About Tungsten (or Wolfram)

Symbol: W
Atomic Number: 74
Appearance: A shiny, silvery-white metal.
Ores: Scheelite and Wolframite.
Unique Properties:
- High Melting Point: Highest melting point of all metals at 3,422°C (6,192°F).
- High Density: Density of 3 g/cm³, comparable to gold.
- Hardness: Very hard, especially when alloyed with other metals (measured as 5 on the Mohs scale).
- Excellent Thermal and Electrical Conductivity: High resistance to thermal expansion.
- Corrosion Resistance: Resistant to oxidation and most acids.
- High Tensile Strength: Retains strength at high temperatures.
- Low Vapor Pressure: Does not vaporize easily, even at high temperatures.

Do you Know?

The Mohs scale is a qualitative scale that measures the scratch resistance of minerals on a scale of 1 to 10.
Lowest Ranking (Softest):
- Talc – Ranked 1
  - Talc is easily scratched and feels greasy.
  - Used in talcum powder and as a lubricant.
Highest Ranking (Hardest):
- Diamond – Ranked 10
  - Diamond is the hardest naturally occurring material.
  - It can scratch all other minerals.
  - Used in cutting tools, abrasives, and jewellery.

Real-world Applications of Tungsten

Electronics and Electrical Industry:
- Filaments in incandescent and halogen bulbs due to its high melting point.
- Electrodes in gas tungsten arc welding (GTAW) due to its high conductivity.
- Semiconductors and X-ray tubes because of its ability to withstand heat.
Aerospace and Defense:
- Used in high-speed aircraft, missiles, and rocket engine nozzles for its heat resistance.
- Armor-piercing projectiles and radiation shielding due to its high density.
Manufacturing and Machining: Tungsten carbide (WC), an incredibly hard compound, is used in:
- Cutting tools, drills, and milling instruments.
- Mining tools, wear-resistant parts, and abrasives.
Medical Sector:
- Radiation shielding in medical imaging (X-rays, CT scans).
- Medical electrodes in surgical instruments.
Jewelry: Tungsten carbide rings and accessories due to their scratch resistance and durability.
Automotive:
- High-performance engines and braking systems.
- Counterweights for balancing vehicles.
Chemical Industry: Catalysts in chemical reactions and petroleum refining.
Sports and Recreation: Fishing weights, darts, and golf club heads due to its density and durability.

Fact

In India, the total tungsten reserves have been estimated to be 87.39 million tonnes.
Main reserve at Degana, Rajasthan.
Tungsten resources in India are mainly distributed in Karnataka (42%), Rajasthan (27%), Andhra Pradesh (17%), and Maharashtra (9%).
The remaining 5% of resources are in Haryana, Tamil Nadu, Uttarakhand, and West Bengal.
Tungsten is one of the 30 critical minerals in India.

UPSC PYQ

Q. Consider the following minerals: (2020)