This pyramid is an example of a (squashed) oct-tet truss (use Green Lines to build Bucky Fuller's version). How many tetrahedra (4 triangular faces) are there? How many octahedra (8 triangular faces) can you find? One of our favorite numbers, the Golden Mean, is found in the Great pyramid of Giza -- but you can't build it with the Zometool. Waaah!!