Acronym	gisp
Name	great swirlprism
Cross sections	©
Circumradius	(sqrt(5)-1)/2 = 0.618034
Colonel of regiment	sub-regimental to gishi
Face vector	120, 720, 720, 120
Confer	uniform relative: gax   padiap   segmentochora: starppy   related scaliform: sisp   general polytopal classes: noble polytopes
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This one can be obtained by chopping off the vertices of a gishi in a similar way along cycles, as is done for padiap. Accordingly those vertex pyramids (gikepy) would intersect themselves, resulting in starppy instead. Instead of using just 2 cycles (as for padiap), here 12 such swirling cycles are used, leaving no tet any more.

The gisp vertex figure is a faceting of gike, having 10 (x,x,x,v)-disphenoids (trapezium with crossed laterals).

As abstract polytope gisp is isomorph to sisp, thereby replacing pentagrams by pentagons, resp. replacing starp by pap.

Incidence matrix

120 |  10   2 |  15   5 |  10
----+---------+---------+----
  2 | 600   * |   2   1 |   3
  2 |   * 120 |   5   0 |   5
----+---------+---------+----
  3 |   2   1 | 600   * |   2
  5 |   5   0 |   * 120 |   2  : {5/2}
----+---------+---------+----
 10 |  15   5 |  10   2 | 120  : starp