The isosohedron and dodecahedron geometries have a unique relation to Phi. When three rectangles of Phi proportion, are set on XYZ axis, their corners touch all the corners of an isosohedron. When three rectangles of Phi² proportion are set on an XYZ axis they touch all corners of a dodecahedron, except for those eight which are touched by the corners of a cube of Phi proportion.