Soil
Soil is the upper layer of the Earth where plants grow.
- Composition: Contains small pebbles, sand, clay, organic matter (decayed plants/animals), air, water, and living organisms like earthworms.
- Formation: Formed by the disintegration (breaking apart) of rocks by the Sun, water, wind, and living organisms over thousands of years.
- Earthworms: Known as “natural agents” that loosen the soil, allowing air to penetrate to the roots.
Rocks
Rocks are hard solid materials found in nature.
- Uses: Construction of houses, temples, dams, and roads.
- Examples:
- Granite, Sandstone, Marble: Building materials.
- Slate: Roofing.
- Laterite: Making bricks.
- Historical Use: Early humans made tools like hand axes and arrowheads from stone.
Minerals
Rocks are made up of minerals. We extract valuable metals from these minerals.
- Examples: Gold, Silver, Copper, Iron, Aluminum.
- Uses:
- Electronics: Mobile phones contain gold, silver, copper, and cobalt.
- Transportation: Aluminum is used in airplanes; Iron/Steel in cars.
- Daily Life: Jewelry, cosmetics, electrical wires.
Warning
Resource Alert: It takes millions of years to form rocks and minerals. They must be used responsibly.