A characteristic of this later, more sophisticated mural art was the use of decorative features such as frames, borders and geometrical patterns, which might accompany the theme of the painting and help it sit comfortably in the architecture that it decorated.
In modern times we still see murals being painted, but now often as political propaganda or commercial advertising. The availability of wallpaper and other commercial decorative features has made painting an expensive option but fortunately there still exists a market for purely decorative murals. In popular culture spray can graffiti has created its own heritage of mural art.
The late Greek and Roman period discovered the decorative the use of trompe l’oeil – that is making a flat wall surface seem as if it is 3D architecture, simply by painting it on with light and shade. Impossible architectural fantasies became possible in the hands of an artist. In Pompeii and Herculaneum there are many surviving murals using fantastic trompe l’oeil. The technique really came into it’s own in the Renaissance period. Ceilings became decorated as skies full of clouds and cherubs, walls had balustrades and pillars giving onto fantastic landscapes with battles raging and mythological creatures roaming. In the hands of the great Italian masters churches and palaces were decorated with masterpieces in this style at which we still marvel today.
The techniques of the earliest painters were not necessarily best for the survival of their works. The cave painters most probably drew directly onto the rock with blocks of pigment or charcoal, using no medium to adhere the paint to the surface. Where examples survive, such as Lascaux in France, the limestone ground has become calcinated with natural dampness over time and has spontaneously adhered the pigment to the wall.
It is known that the Ancient Egyptians had Gum Arabic (resin from the Acacia tree – which we still use as the binder for watercolours). They also used egg tempera (pigment bound with the white of an egg). Most importantly where murals are concerned, they understood how to paint ‘fresco’. That is, painting raw pigment into fresh lime plaster before it dries. Most surviving murals of antiquity and the renaissance have used this technique. The great advantage of this technique is that the pigment colour combines with the natural calcination of the plaster as it dries, so it never fades. Subsequently, the technique of fresco was passed down from Greek to Roman and Roman to the Renaissance, so it has left us with a rich legacy of ancient art with which to understand the psychology and wisdom of our ancestors.