Here's why:

* Soil Texture: Soil texture refers to the relative proportions of sand, silt, and clay particles.

* Particle Size: Clay particles are the smallest, with diameters less than 0.002 millimeters. This makes them incredibly fine and often difficult to see without a microscope.

* Properties: Clay particles have a large surface area, which allows them to hold onto water and nutrients more effectively than sand or silt. They also contribute to soil's plasticity and stickiness.

Let me know if you'd like to know more about soil texture or the properties of clay!