This is a beautiful set of the 5 Platonic Solids plus the equally if not more important Vector Equilibrium.
Buckminster Fuller was the one who named the Vector Equilibrium and recognised its nature as the perfec balance of contractive and expansive forces. It's vertexes show the natural way that spheres cluster, with 12 points equally distant from their neighbors and from the central point. It is the 3d equivalent of the hexagon, showing the same symmetry as the 6 circles surrounding a central circle as they do in the Flower of Life.