The extraction of halide minerals like halite (rock salt) and fluorite (fluorspar) depends on their geological formation, depth, and economic viability. The most common extraction methods include:

1. Halite (Rock Salt) Extraction Methods

A. Underground Room and Pillar Mining (Most Common for Rock Salt)

  • Method:
    • Large rooms are excavated, leaving behind “pillars” of salt to support the mine.
    • Mechanical equipment like continuous miners or drills and blasting is used to extract the salt.
  • Used For: Industrial salt, de-icing, and chemical production.
  • Example Sites:
    • Sifto Salt Mine, Canada (World’s largest underground salt mine).
    • Goderich Salt Mine, USA.

B. Solution Mining (Brine Extraction)

  • Method:
    • Water is injected into underground salt deposits, dissolving halite.
    • The brine (saltwater) is pumped to the surface and evaporated to extract pure salt.
  • Used For: Table salt, industrial chemicals (chlorine, soda ash).
  • Example Sites:
    • Great Salt Lake, USA.
    • Dead Sea, Israel & Jordan.

C. Solar Evaporation (For Salt Flats and Lakes)

  • Method:
    • Saltwater from oceans, lakes, or artificial ponds is evaporated using sunlight.
    • The remaining salt is harvested.
  • Used For: Food-grade salt, industrial salt.
  • Example Sites:
    • Salar de Uyuni, Bolivia.
    • Salar de Atacama, Chile.

2. Fluorite (Fluorspar) Extraction Methods

A. Open-Pit Mining (For Surface Deposits)

  • Method:
    • Large-scale excavation of fluorite veins using drilling and blasting.
    • Ore is transported to a processing plant for crushing and beneficiation.
  • Used For: Metallurgy (steelmaking flux), glass and ceramics.
  • Example Sites:
    • Mongolia, China, South Africa (Vergenoeg Mine).

B. Underground Mining (For Deep Fluorite Deposits)

  • Method:
    • Shafts and tunnels are created to access high-grade fluorite veins.
    • Conventional room and pillar or cut and fill mining techniques are used.
  • Used For: High-purity fluorite for hydrofluoric acid, refrigerants, and aluminum processing.
  • Example Sites:
    • Illinois-Kentucky Fluorspar District, USA.
    • Okorusu Fluorite Mine, Namibia.

C. Beneficiation and Processing

  • After extraction, fluorite undergoes processing:
    • Crushing & grinding to reduce ore size.
    • Flotation separation to remove impurities.
    • Drying and refining for marketable grades.