This is a 120mmx190mm clamshell egg inspired by the egg in Harry Potter and the Goblet of Fire. It features a print in place hinge. I used automatic supprts in Simplify 3d and then removed the ones over the hinge joint lines. I printed upright at 0.2mm layer height and 30% infill. I used MakerGeeks Gold PLA but it came out a bit more peachy than I wanted so I sanded, primed, and painted it with Rustoleum Metallic Champange Bronze. I press fit two magnets in the holes at the top of the egg. Depending on the magnets this might be a tight fit. I've also included an inner egg. I printed mine in PETG that I did not dry. This resulted in a white textured appearance. There is a 50mm hole in the bottom to both fit over the hinge and provide access to the interior to allow for fairy lights inside.

I uploaded a file for a plain STL that I produced by suppressing features in Fusion 360. It should be fine but I did not print this version.

I went through several versions of this before settling on this hinge. In the first version I had a slimmer hidden hinge which worked well on partial prints but did not work on full prints because it bound up. I think this was due to the long print time and close proximity of the hinge to the heated plate causing adhesion. I also learned its way to hot in Arizona to leave the model in the sun. There were no problems with the white primer coat but it warped significantly with the gold top coat. I was able to bodge it back in place with gentle heating.