Polyhedral Version
This is the famous Roman surface of Steiner, named after him because he invented it in Rome, after a visit to the Colosseum. Unilateral, like the Boy and the Crosscap, it is yet another face of the "
". It has a triple point at the center and six cusp points. Steiner surfaces are generally constructed with recovered Whitney umbrellas. Its equation of the fourth degree is surprisingly simple:
- 2 x y z = 0