Two Polyhedral Compounds

Compound of the RTC and a strombic hexacontahedron

The image above is a compound of the rhombic triacontahedron (the dual of the icosidodecahedron) and a strombic hexacontahedron (the dual of the rhombicosidodecahedron). Below, you’ll find a compound of six square-based pyramids, all with their “centers of mass” (assuming uniform density) displaced, from the compound’s center, by equal amounts. In response to a request I have received, polyhedral images which rotate more slowly are coming soon . . . after I have finished posting my backlog of already-produced polyhedral .gif files, since there is no way to slow them down after they are already created.

Compound of Twelve Square-based pyramids

The program I use for these polyhedral investigations is Stella 4d, available at

A Strombic Hexacontahedron, Augmented with Sixty More Strombic Hexacontahedra

Strombic Hexecontahedra augmented with 60 strombic hexacontahedra

The faces of the strombic hexacontahedron, the dual of the rhombicosidodecahedron, are kites. I have no explanation for why the word “strombic” applies to it — is a kite a “stromb?”

I’ve already googled it, followed many links, etc., and it’s still as puzzling to me as it was the first time I read it. If you have a solution to this puzzle, please post it in a comment.

Software used to create this image:  Stella 4d:  Polyhedron Navigator, available at