Throughout his plastic research, Ángel Mateos gradually developed a constant process of purification of form. In several series he had reached a high degree of simplicity in his sculpture, but his research based on the single plane had only one consistent end: minimalism.
In 1974 Mateos began to work with the single plane, giving rise to several series, Menhires and Flexiones, and in 1979 he resumed this research with this series which he generically called Verticales. In it Mateos worked analytically on the expressive possibilities of the plane, giving rise to the four pairs that make up this series: Homages, Twists, Neoliths and Pylons. In some of these, the principle of minimal intervention is taken to its maximum expression, and simplicity and subtlety are their common denominator.
At the same time, over the years he has developed a profound knowledge of the technique of concrete, which allows him in this series to take the material to the limit of its structural possibilities. Concrete has ceased to be a simple material for Mateos, and has become a true artistic medium, from which the monumental power of his work derives. As the sculptor said, "Concrete is the most representative material of this era, and just as stone defined an era, this will be the age of concrete".