Algae spread through the whole mass and behave like a gel, which facilitates deformation. The effect is equivalent to other organic and inorganic colloids, which by their swelling behaviour increase their plasticity. However the effect is lesser than that of humic acid which is able to break down clay aggregates into individual lamellae.
To sum up, the following are the essential elements that contribute for plasticity.
1. The presence of small charged particles
2. The lamellar form of clay particles
3. The large surface area for the formation of water films
4. The surface tension of water
The water has the highest surface tension of all liquids and is responsible for its capillary properties which reveal themselves in the rising sap in trees, in the pores of a plaster mould and in the capillary network of a wad of clay.
To be contd…………..
