"The Crystal," by Sulamith Wulfing.
Note that in traditional Western symbolism, the icosahedron is identified with the classical element of water, which in turn is identified with—among other things—the womb, and the reproductive system generally. Thus, the child in the icosahedron is, I don't know, some sort of child-archetype or something. I would be interested in knowing more about this piece. It is open to a pretty wide range of interpretation. It is also hexagonal.