SILT is a very small rock fragment or mineral particle, smaller than a very fine grain of sand and larger than coarse clay; usually described as having a diameter from 0.002 millimeter to 0.06 millimeter.
Soil is made of particles of various sizes. Silt, a
constituent of soil, comprises particles of sizes between
those of clay and sand. According to the international
particle-size system, a silt particle size is about 2 to 50 pm
in diameter. It is further divided into fme silt (2 to 20 pm)
and coarse silt (20 to 50 pm). The percentage of silt
particles in a particular soil is taken into consideration
while defining soil texture.
Silt is often carried as suspended particles in running
water and deposited on riverbeds, riverbanks or in lakes
as alluvial sediments.
A soil that contains 40% or more of clay and 40% or
more of silt is called silt clay. A soil with 27 to 40% clay
and less than 20% sand is known as silt-clay loam. Silt
loam has 30% or more silt and 12 to 27% clay. Similarly,
silt loam soil consists of 50 to 80% silt, less than 12%
clay and the rest sand.
