# Back in Shape

Simon prepared 100 2D shapes to make over 100 solids yesterday. He started with the easy one that he had built hundreds of times before, when he was much younger (like the Platonic Solids and some of the Archimedean Solids and anti-prisms), but then went on to less familiar categories, like elongated and gyroelongated cupolae and dipyramids! Never heard of a Gyrobifastigium? Take a look below!

Dodecahedron

Icosahedron

Cuboctahedron

Small Rhombicuboctahedron (by expanding a cube)

Icosidodecahedron

Simon didn’t build a snub cube (“is a real challenge and has two different versions that are mirror images of each other”). Nor did he make a truncated dodecahedron (as he has no decagons), nor a truncated icosahedron (doesn’t have 20 hexagons). “If you slice the corners off of an icosahedron, you get a truncated icosahedron also known as a… football!” The 62-sided rhombicosidodecahedron he had already made many times before, we’ll post an old photo later.

And then came the antiprisms:

A square antiprism – two squares connected with a band of equilateral triangles

A pentagonal antiprism

And the elongated shapes:

Pentagonal cupola (half a cantellated dodecahedron); there is no hexagonal cupola

Pentagonal rotunda (half of an icosidodecahedron)

Gyroelongated triangular pyramid

Gyroelongated square pyramid

“If you gyroelongate a pentagonal pyramid, it looks like an icosahedron, but isn’t quite that”:

Gyroelongated pentagonal pyramid

Elongated square dipyramid

Elongated triangular cupola

Gyroelongated triangular cupola

Gyrobifastigium (there it is, you found it!)

Square orthobicupola

Pentagonal orthobicupola (above) and its twisted variant – pentagonal gyrobicupola (below), looking like a UFO