Icosahedra have twenty faces. In the image above, only twelve of those triangles are visible; the other eight have been hidden, so you can see what this solid looks like on the inside. The twelve which remain have pyritohedral symmetry — the symmetry of a volleyball.
I made this using Stella 4d, which you can try for free at http://www.software3d.com/Stella.php.
mesmerizing and beautiful and original— thank you for your geometric./mathematical artwork– i always look forward to seeing what you will invent next!
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