Triangular tegum

The triangular bipyramid, also called a triangular dipyramid, is a bipyramid with a triangle as the equatorial section. Generally,a trianuglar bipyramid has 6 identical isosceles triangles as faces. It can be formed by joinig two triangular pyramids at their bases.

Two specific cases of the general triangular bipyramid are notable. One such variation is obtained as the ddual to the uniform triangular prism. The other is one of the Johnson solids, due to the pyramids being regular tetrahedra.