Johnson Solids (Page 2)

(box: x-ray)  (F: faces)  (slider: perspective)  (image: L=rotate R=zoom)  (M: metrics)

(J21) Elongated Pentagonal Rotunda
Vertices:  30  (10[3] + {10 + 5 * 2}[4])
Faces:27  ({5 * 2} equilateral triangles + {5 * 2} squares
    + {5 + 1} regular pentagons + 1 regular decagon)
Edges:55
Symmetry:  5-fold Pyramidal  (C5v)
(values below based on edge length = 1)
Volume:(45+17*sqrt(5)+30*sqrt(5    
    +2*sqrt(5)))/12    
≈14.611971811062835576