Tetrahedron

Tetrahedron Vertex Truncation

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Tetrahedron Vertex Truncation becomes Octahedron

Tetrahedron Edge Truncation

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Tetrahedron Edge Truncation transforms it into cuboctahedron and then ends up as its own dual, tetrahedron again.

Tetrahedron Snub Truncation

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Tetrahedron Snub Truncation morph into Icosahedron

Tetrahedron and Cube Relation

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Tetrahedron can be changed into a cube by triangulate each face and extend it outward.
tetrahedron edge truncation dual 37266 tetrahedron edge truncation dual 54017
cuboctahedron and its dual the rhombic dodecahedron (in wireframe)
tetrahedron vertex tr in dual tetrahedron trunc in dual
vertex truncated tetrahedron and its dual (in wireframe)
tetrahedron as stoneball
tetrahedron as stoneball