A beautiful and challenging puzzle. The arcs on every piece have the same radius as the outer circle, thus any pc could potentially match along the outer edge or adjacent to any other pc where a concave curve meets a convex curve. But, there is only one solution!
Hint: The solution is engraved in on the backside.
I recommend printing puzzles in four different colors. It looks amazing.
Enjoy!
The author hasn't provided the model origin yet.