There are many instances where wet sieving, despite its attendant inconveniences, has a distinct advantage over dry sieving. For example, the material to be tested may already be suspended in a liquid. Solids in slurry form are often sized by wet screening.
Samples of wet solids, such as treated ores or chemical precipitates, frequently contain some very fine particles which constitute a slime. These samples cannot be dried before sieving
because the slime would cake into hard lumps. Wet sieving affords an easy method for removing and sizing these fine particles.