Non-metallic minerals, such as limestone, gypsum, clay, phosphate, and silica sand, are extracted using methods that vary based on their geological formation and intended use. The primary extraction techniques include:
- Surface Mining (Quarrying & Open-Pit Mining)
- Quarrying: Used for extracting large, massive deposits such as limestone, marble, and granite. Involves drilling, blasting, and cutting.
- Open-Pit Mining: Common for softer minerals like phosphate and clay. It involves removing overburden and extracting mineral-rich layers.
- Strip Mining
- Used for extracting minerals like phosphate, clay, and potash from shallow, horizontal deposits.
- Involves stripping layers of soil and rock to expose minerals.
- Solution Mining (In-Situ Leaching)
- Commonly used for soluble minerals like salt (halite) and potash.
- A solvent (usually water) is injected into underground deposits to dissolve minerals, which are then pumped to the surface.
- Dredging
- Used for sand, gravel, and some clay deposits found in riverbeds and coastal areas.
- Involves using specialized equipment to extract minerals from underwater deposits.
- Underground Mining
- Used for non-metallic minerals with deeper deposits, such as certain types of salt and gypsum.
- Includes room-and-pillar and longwall mining techniques.
