Acronym  rastacu 
Name 
retrograde pentagrammic cupola, 5/3cupola 
Circumradius  sqrt[sqrt(5)+11/4] = 0.716891 
Vertex figures  [3,4,5/3,4], [3,4,10/3] 
Dihedral angles 

Confer 

As abstract polytope rastacu is isomorphic to pecu, thereby replacing the retrograde pentagram by a (prograde) pentagon and the decagram by a decagon. Or it is isomorphic to stacu, thereby replacing the retrograde pentagram by a prograde pentagram and the decagram by a Grünbaumian {10/2}.
This polyhedron is an edgefaceting of the great dodekicosidodecahedron (gaddid).
Incidence matrix according to Dynkin symbol
xx5/3ox&#x → height = sqrt((5+sqrt(5))/10) = 0.850651
({5/2}  {10/3})
o.5/3o.  5 *  2 2 0 0  1 2 1 0
.o5/3.o  * 10  0 1 1 1  0 1 1 1
+++
x. ..  2 0  5 * * *  1 1 0 0
oo5/3oo&#x  1 1  * 10 * *  0 1 1 0
.x ..  0 2  * * 5 *  0 1 0 1
.. .x  0 2  * * * 5  0 0 1 1
+++
x.5/3o.  5 0  5 0 0 0  1 * * *
xx ..&#x  2 2  1 2 1 0  * 5 * *
.. ox&#x  1 2  0 2 0 1  * * 5 *
.x5/3.x  0 10  0 0 5 5  * * * 1
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