By George Hart for the Museum of Mathematics


The icosahedron consists of twenty equilateral triangles, meeting five at each vertex. Here are two icosahedron constructions you can make from soda bottles. These were designed and built by Mario Marin, whose web site shows many creative ways to recycle household objects into polyhedral structures.


Pairs of cut bottles are joined here to make “double bottles” which are used as the thirty edges of an icosahedron. The twelve yellow “flowers” are cut from plastic sheet, with holes that are locked into place by screwing on the bottle tops.


This lamp construction is built around a cardboard icoshadron as its core. A hole in each of the twenty bottle tops allows wires to pass through to power the small light in each bottle.