• (p. pr. & vb. n.) of Crust
sealing of the soil surface by fine soil particles. These block the larger pores, reducing the movement of gases into and from the soil and reducing the penetration of water.
Also known as scab, is dried blood, pus, or other fluids on the surface of the skin.
the result of plasma exuding through an eroded epidermis. It is rough on the surface and is yellow or brown in colour. Bloody crust appears red, purple or black. 
Formation of dry crust on surface of doughnuts due to evaporation of water from the surface.
Varying colors of liquid debris (serum or pus) that has dried on the surface of the skin.
Also known as a scab, is dried blood, pus, or other fluids on the surface of the skin.