Bisected Tetrahedron
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See the related Tirsected Cube Puzzle
Bisected Tetrahedron Puzzle: two identically shaped pieces interlock to form the famous four faced platonic solid in this ingenious dissection puzzle. The tetrahedron is sliced following a helical path along the 2-fold symmetry axis (middle of one edge to its opposite), creating a smooth disassembly, and a smooth but mildly challenging reassembly. Fun math today from puzzle maker, artist, and mathematician George Hart.