These are the 3D version of our shapes of constant width. Amazingly, they are the same width no matter how you orient them, which you'd think was only true of spheres. Manufactured by The Matter Collection, these solids are made from solid metal, and are available in a selection of finishes and colours.
You can make a solid of constant width by rotating a shape of constant width, to get a solid of rotation. That's pretty cool, but a bit boring. These solids are derived from the 3D equivalent of a triangle, a tetrahedron, by replacing each triangular face with a section of the surface of a sphere centred at the opposite point of the tetrahedron. The edges are then smoothed out using a shape based on an envelope of spheres along the edge, to produce a spheroform - a geometric wonder, and a fascinating object.
Why a set of 3? Well, if you put all 3 under a large book and roll them around the book will remain at a constant height from the desk. You won't be able to tell that they aren't spheres!
Price = p1229 pence = £99.73