Shows the central prolate rhombohedron highlighted - the only one with all its faces inside the triacontrahedron.
There are three oblate rhombohedra touching it which are also entirely within the triacontrahedron. Two of those, together with another prolate rhombohedron, make a golden rhombic dodecahedron with one face exterior to the triacontrahedron (the exterior face is the one at the bottom of this picture, which you see almost edge on).
.The rhombic dodecahedron, triacontrahedron, and golden rhombohedra.
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