
 Great Rhombicosidodecahedron 
 Vertex description: 4.5/3.4.3
 Faces: 62
 Edges: 120
 Vertices: 60
 External facelets: 980
 Dual: Great strombic hexecontahedron
This is the dual of the great strombic hexecontahedron. It has 980 external
facelets to put together! Each vertex is surrounded by a triangle, a square, a
pentagram, and finally another square which crosses back through the first one.
Over two months passed making this model! I was also busy with other projects
though, and even made some other models along the way, so it could be made much
quicker.
Note: some people use the name "great rhombicosidodecahedron" to refer to
the truncated icosidodecahedron, which
confuses things somewhat!

You'll be making lots of these. 60 in fact. Five of these are
required for the part below.


This is how I started, although I'd now recommend putting in the purple
triangle pairs last. The parts above meet each other at a
pinched edge, where the squares pass through each other. Using
nets from
Great Stella,
there should be an alreadyglued tab on one part at these pinched
edges, which can be glued under a face of the other part, adding
strength.


Here is the same part upsidedown. A part like this was also last to
be put in, minus the purple triangle pairs, and without gluing the
pinched edges together until the whole piece was in place on the final
model. Then attaching the last five triangle pairs completes the
model.


You'll also need 20 of this part, to connect the above parts together.


Starting to take form.


More than half way now!


The completed model, viewed down a 5fold rotational symmetry axes.


The view down a 3fold rotational symmetry axes.


The view down a 2fold rotational symmetry axes.


Here's a closeup shot of the detail in the model.


Another closeup.


Another closeup.


These three models are related to each other. They all share the same
set of vertices and edges. Four faces surround a vertex in each model,
and you may think of these as being two pairs, chosen from a set of
three available pairs: (1) a pair of decagrams, (2) a triangle and a
pentagram, and (3) a pair of intersecting squares.
The great dodecicosidodecahedron
has pairs (1) & (2).
The great rhombidodecahedron
has pairs (1) & (3).
The great rhombicosidodecahedron has pairs (2) & (3).

