category	diameters of the particules	1µm = 0.001 mm
coarse sand	2 mm to 200 µm
fine sand	200 µm to 50 µm
very fine sand	50 µm to 20 µm
silt	20 µm to 2 µm
clay	less than 2 µm

In which category is classified
a particle which diameter is