Hyper-tetrahedron Tetrahedral prism model
That is a model I made back in ~2013 with paper clips.
Back then I attempted to build tiny chain reactions (marble tracks) at the wall of my room. I remember building a cube-like marble releaser using only sticks and tie. - Cubes are not stable like tetrahedra when only using sticks for the main edges. Without additional edges the cube could be distorted by torsion. This made it annoying as it resulted in needing far more sticks to stabilize. -> Tetrahedra are more efficient in these aspects.
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The molecular structure of diamonds is also tetrahedral. (It could also explain why diamonds are so hard/stable. )
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hyper-tetrahedron/5-cell/4-simplex (Left) and tetrahedral prism (Right):
