Believe it or not, this is a mathematical equation you are looking at. This is another model by Dizingof, a very talented 3D artist.
This was printed in ABS at 0.15mm layer height, then treated with acetone vapor to give it a smooth finish.
A time-lapse video of the print can be found here. This is one of my favorite time-lapse videos. It’s kind of like watching a sunrise!