Compound of two great icosahedra

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Short description: Polyhedral compound
Compound of two great icosahedra
UC52-2 great icosahedra.png
Type Uniform compound
Index UC52
Polyhedra 2 great icosahedra
Faces 16+24 triangles
Edges 60
Vertices 24
Symmetry group octahedral (Oh)
Subgroup restricting to one constituent pyritohedral (Th)

File:Compound of two great icosahedra.stl In geometry, the compound of two great icosahedra is a uniform polyhedron compound. It's composed of 2 great icosahedra, in the same arrangement as in the compound of 2 icosahedra.

The triangles in this compound decompose into two orbits under action of the symmetry group: 16 of the triangles lie in coplanar pairs in octahedral planes, while the other 24 lie in unique planes.

The great icosahedron, as a uniform retrosnub tetrahedron Retrosnub tetrahedron.png, is similar to these snub-pair compounds: compound of two icosahedra, compound of two snub cubes and compound of two snub dodecahedra.

References

  • Skilling, John (1976), "Uniform Compounds of Uniform Polyhedra", Mathematical Proceedings of the Cambridge Philosophical Society 79 (3): 447–457, doi:10.1017/S0305004100052440 .

External links