The soil matrix is the solid phase of soils, and comprise the solid particles that make up soils. Soil particles can be classified by their chemical composition (mineralogy) as well as their size. The particle size distribution of a soil, its texture, determines many of the properties of that soil, in particular hydraulic conductivity and water potential,[1] but the mineralogy of those particles can strongly modify those properties. The mineralogy of the finest soil particles, clay, is especially important.[2]