Slide-Together Construction (30 elements)
The basic structure is the icosidodecahedron. It is more complex than the cuboctahedron (the basic structure for the 12 element slide-together structure) and impossible to take apart the elements, but also fairly easy to assemble. The icosidodecahedron is composed of the 20 triangular faces of the icosahedron and the 12 pentagonal faces of the dodecahedron, which is the polyhedron dual of the icosahedron.