Triangular dipyramid
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Template:Infobox face-uniform polyhedron
In geometry, the triangular dipyramid is one of the Johnson solids (J12). As the name suggests, it can be constructed by joining two tetrahedra along one face. It is a convex deltahedron. Although all its faces are congruent and the solid is face-uniform, it is not a Platonic solid because some vertices adjoin three faces and others adjoin four.
The 92 Johnson solids were named and described by Norman Johnson in 1966.
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