Silt is a granular material composed of the minerals feldspar and quartz. It is found suspended in bodies of water, as sediment in bodies of water, or as a soil.
Based on particle size, silt falls between Clay (smallest particles) and Sand.
The particles of Clay, unlike the larger and uniform granules of silt, are plate like and adherent to one another (cohesive). Sand particles, like those of silt, are uniform, but larger.
The water storage capacity of rock/sediment/soil materials depends on the amount of interstitial space between the soil’s particles. As it turns out, the water storage capacity of these materials is directly proportional to their particle sizes, arranged in descending order as follows:
Gravel (highest water storage)
Clay (least water storage)