The 120 Polyhedron

The (x, y, z) coordinates for all of the vertices can be put into the form
n φm
where n = -2, -1, 0, 1, 2 and m = -1, 0, 1 and φ is the Golden ratio.

Vertex Type X Y Z
1 A 0 0 2
2 B 1 0 φ
3 A φ-1 1 φ
4 C 0 φ-1 φ
5 A -1 1 φ
6 B -1 0 φ
7 A -1 -1 φ
8 C 0 -1 φ
9 A φ-1 -1 φ
10 A φ φ-1 1
11 C 1 1 1
12 B 0 φ 1
13 C -1 1 1
14 A φ-1 1
15 A -1 1
16 C -1 -1 1
17 B 0 1
18 C 1 -1 1
19 A φ -1 1
20 C φ 0 φ-1
21 A 1 φ φ-1
22 A -1 φ φ-1
23 C 0 φ-1
24 A -1 φ-1
25 A 1 φ-1
Vertex Type X Y   Z  
26 A 2 0 0
27 B φ 1 0
28 C φ-1 φ 0
29 A 0 2 0
30 C -1 φ 0
31 B 1 0
32 A -2 0 0
33 B -1 0
34 C -1 0
35 A 0 -2 0
36 C φ-1 0
37 B φ -1 0
Vertex Type X Y Z
38 C φ 0 -1
39 A 1 φ -1
40 A -1 φ -1
41 C 0 -1
42 A -1 -1
43 A 1 -1
44 A φ φ-1 -1
45 C 1 1 -1
46 B 0 φ -1
47 C -1 1 -1
48 A φ-1 -1
49 A -1 -1
50 C -1 -1 -1
51 B 0 -1
52 C 1 -1 -1
53 A φ -1 -1
54 B 1 0
55 A φ-1 1
56 C 0 φ-1
57 A -1 1
58 B -1 0
59 A -1 -1
60 C 0 -1
61 A φ-1 -1
62 A 0 0 -2

φ = (1 + √5) / 2 = 1.618033989...
φ-1 = φ - 1 = 0.618033989...

Type "A" = Octahedron vertex
Type "B" = Icosahedron vertex
Type "C" = Tetrahedron, Cube, Dodecahedron vertex  

Note the z-components are 2, φ, 1, φ-1, 0, -φ-1, -1, -φ, -2.
This defines 9 layers or planes (in this orientation of the 120 Polyhedron).


The Cube's 4 vertex-to-opposite-vertex axes were used
for the Cube and Octahedron's rotations.

What are the rotation angles?

|α| + |β| = 120°


For an arbitrary (x, y, z) coordinate, if rotated by these angles
what is the resulting coordinate (x', y', z')?


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Copyright September, 2007 by Robert W. Gray