There are five platonic solids, the tetrahedron, cube, octahedron, dodecahedron and icosahedron. A prism is a 3D shape with a constant polygon shaped cross-section. A prism is named by the shape ...

are all made out of some kind of metal alloy (e.g. bronze), are usually a dodecahedron but sometimes different (e.g. an icosahedron with 20 faces), yet all are hollow and usually with a single ...

Regular Octahedron National Museum of American History Polyhedron Model by Martin Berman, Cube National Museum of American History Polyhedron Model by Martin Berman, Regular Icosahedron ...