Aluminum soaps are used for waterproofing. Formerly, extracts of wood ashes were used. Potassium gives soft soaps and sodium gives hard soaps. Detergents often are made by sulfonation of other types of organic molecules usually. Saponins from plants are often used in some societies as soap or detergent substitutes.
Coconut oil is still the most commonly used oil for soap.
Paints Many polyunsaturated oils are incorporated with pigments into paints and varnishes. Linseed oil and tung are among the most common of this type. The Flemish combined pigments and oils to make oil paints in the 15th century. They also perfected technique of painting over the pictures with glazing, and translucent coatings over an undercoating in order to give an illusion of depth. See the diagram on page 298.