Clay also makes the hair soft.
Clay has a little to no shine, meaning a stylist can achieve a very natural and dull look.
Typically, the clays will give the product a gritty feeling in the hand, and make the product thicker and heavier than other creams or pastes.
Most clay products are considered salon grade, and the price of these products is usually more expensive than normal consumer level hair wax and gel.
That is, they can leave visible streak marks on the hair if applied poorly.