* Rock Weathering: Over time, rocks are broken down by physical and chemical processes (like wind, water, ice, and chemical reactions) into smaller particles.
* Particle Size: Sand, silt, and clay are categorized based on their particle size.
* Sand: The largest particles, easily visible to the naked eye.
* Silt: Smaller than sand, but still visible with a magnifying glass.
* Clay: The smallest particles, only visible with a microscope.
* Mineral Composition: These particles are primarily composed of minerals that were originally present in the parent rocks. They are not organic materials like those found in humus.
Mineral soil contrasts with organic soil which is primarily composed of decayed plant and animal matter. While mineral soil can contain some organic matter, the majority of its composition is derived from weathered rock.
In summary: Sand, silt, and clay are considered mineral soil because they are:
1. Derived from weathered rocks: Their primary source is the breakdown of geological materials.
2. Mineral-based: They are composed of minerals, not organic matter.
3. Classified by particle size: Their differences lie in the size of the mineral particles they contain.
