Velvet or leather (color of choice, optionally fire-proof)
Designing an armchair while thinking, as Vitruvius said, that everything we do has to be solid, useful and pleasing. Planning it around a basic geometrical shape like a circle, which has represented eternity since ancient times, having neither a beginning nor an end. Circles are easy to find in nature, when we throw a stone into water or discover the cross-section of a tree trunk.
The genius of an artist like Giotto was shown by drawing a circle. Baptisteries are ancient works with a circular base like the southern Italian trulli. You can dance in a circle. Sitting in a circular fashion gives rise to the shape of arenas and circuses. In the 1930s, Marcel Duchamp drew spinning discs with particular optical effects. Buckminster Fuller devised geodesic domes in different materials. Here the wood is oak and the padding made of leather or velvet. Eugenio Gerli drew with a pencil or Indian ink on glossy paper in his Milan studio where the magnolias have shiny, plump leaves, as precise as his drawings which do not seem to be made by a human hand. The Milanese architect and designer identified himself with a culture that gave a great deal of importance to manual production. Equally as important was fantasy, always governed, however, through a calculated and exact filter, a mysterious code in its very obviousness.