Catalan Solids

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Pentakis Dodecahedron
canonical form
Vertices:  32  (12[5] + 20[6])
Faces:60  (isosceles triangles)
Edges:90  (60 short + 30 long)
Symmetry:  Full Icosahedral  (Ih)
Dihedral Angle:  acos(−(80+9*sqrt(5))/109)    ≈156.718553726 degrees
Dual Solid:  Truncated Icosahedron
(values below based on unit-edge-length Truncated Icosahedron)
Short Edge (60):  9*(2*sqrt(5)−1)/19    ≈1.6446959786840112913
Long Edge (30):  3*(sqrt(5)−1)/2    ≈1.8541019662496845446
[5]-Vertex Radius (12):  9*sqrt(65+22*sqrt(5))/38    ≈2.53092686862706152146
[6]-Vertex Radius (20):  3*sqrt(3)/2    ≈2.5980762113533159403
Edge-scribed Radius:  3*(1+sqrt(5))/4    ≈2.4270509831248422723
Inscribed Radius:  9*sqrt(109*(17+6*sqrt(5)))/218    ≈2.3771316059838161118
Volume:405*(9+sqrt(5))/76    ≈59.876414880097563514


References:[1]Eugène Catalan, Mémoire sur la Théorie des Polyèdres,
Journal de l'École polytechnique 41 (1865), 1-71, +7 plates.