4.7 Mineral Resources

Mineral resources and mining

Mineral resources are naturally occurring, nonrenewable inorganic substances used for fuel, structural materials, and manufacturing (e.g., metals like copper, aluminum, and iron). They're extracted through surface mining (strip mining, open-pit mining, mountaintop removal) and subsurface mining. Surface mining disturbs more land but is cheaper; subsurface mining is more dangerous but leaves less surface disturbance.

Environmental impacts of mining

Mining causes habitat destruction, erosion, and acid mine drainage — sulfuric acid runoff formed when exposed sulfide minerals react with water and air, contaminating waterways and killing aquatic life. Tailings (waste rock) can leach heavy metals like mercury and arsenic into soil and groundwater. Reclamation efforts attempt to restore mined land but often can't fully repair ecosystems.

Sustainability of mineral use

Because minerals are nonrenewable, sustainable use depends on reduce, reuse, and recycle strategies. Recycling metals like aluminum and steel saves energy, reduces mining demand, and lowers pollution. As high-grade ore deposits are depleted, extracting lower-grade ore requires more energy and creates more waste, making conservation and recycling increasingly important.

Key terms

Mineral resource

A naturally occurring, nonrenewable inorganic substance used for fuel, materials, or manufacturing.

Acid mine drainage

Sulfuric acid runoff formed when sulfide minerals in mines react with water and air, contaminating waterways.

Surface mining

Extraction method that removes overlying soil/rock (strip mining, open-pit, mountaintop removal); disturbs large land areas.

Tailings

Waste rock left after mineral extraction that can leach heavy metals into soil and groundwater.

Sustainable mineral use

Relies on reducing, reusing, and recycling minerals like aluminum and steel to conserve nonrenewable resources.

Try an AP-style question

What is an ore?

1. A type of horizon found in soil
2. Any rock that is found at the surface
3. A fossil fuel buried in sediment
4. Rock with enough mineral to mine profitably