Acronym	gort
Name	great rhombic triacontahedron
VRML	⭳ ©
Inradius	sqrt[(5-2 sqrt(5))/5] = 0.324920
Vertex figure	[r5/2], [R3]
Dual	gid
Dihedral angles (at margins)	between {(r,R)2} and {(r,R)2}:   72°
Face vector	32, 60, 30
Confer	general polytopal classes: Catalan polyhedra
External links

The rhombs {(r,R)²} have vertex angles r = arccos(1/sqrt(5)) = 63.434949° resp. R = arccos(-1/sqrt(5)) = 116.565051°. Esp. rr : RR = (1+sqrt(5))/2.

All a = rr and b = RR edges, provided in the below description, only qualify as pseudo edges wrt. the full polyhedron. Edge size used here is rR = x = 1.

Incidence matrix according to Dynkin symbol

o3m5/2o =
((ao3oo5/2ob))&#zx   → height = 0, 
                       a = rr = 2 sqrt[(5+sqrt(5))/10] = 1.701302, 
                       b = RR = 2 sqrt[(5-sqrt(5))/10] = 1.051462

  o.3o.5/2o.       | 12  * |  5 |  5  [r5]
  .o3.o5/2.o       |  * 20 |  3 |  3  [R3]
-------------------+-------+----+---
  oo3oo5/2oo  &#x  |  1  1 | 60 |  2
-------------------+-------+----+---
((ao ..   ob))&#zx |  2  2 |  4 | 30  {(r,R)2}