Ruffled Rings Origami Tessellation
I'm pretty sure that I tried to do this one a little while back and didn't quite achieve success. Didn't quite figure the reverse side the first time around.
This time I got it quite easily. At least the concept and architecture anyway. The actual execution was another story.
It started out really difficult working from the front side of the paper. However, once I moved to the rear it became a lot easier.
Not easy really, but less frustration, more just folding.
Alternating triangles and rhombuses. The rhombus points are 'eaten' by the triangles flat sides.
Similar technique to that used in Scholz's Triphilia tessellation.
I did save a crease pattern sketch. It's not terribly detailed, but it should be helpful if you're interested.