The Elongated Square Bipyramid

The elongated square bipyramid is the 15th Johnson solid (J15). It has 10 vertices, 20 edges, and 12 faces (8 equilateral triangles and 4 squares).

The elongated square

The elongated square bipyramid can be constructed by attaching two square pyramids to a cube. Its name describes its relation to the octahedron, regarded as the square bipyramid: inserting a cube between the two constituent square pyramids to make the bipyramid longer.


Here are some views of the elongated square bipyramid from various angles:

Projection Envelope Description

Top view.


Side view.


Diagonal side view.


The Cartesian coordinates of the elongated square bipyramid with edge length 2 are:


Due to its relation with the octahedron as a partial Stott expansion, the elongated square bipyramid features as cells in a number of CRF polychora, including (but not limited to):

Last updated 18 Jun 2019.

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