I made this crown a loooong time ago using EVA foam and a laser cutter, so I recreated it with a 3d printer. Basically extrude, and went at it with a sculpting brush :D. It is not 100% lore accurate, more of a stylized version; but it still looks very nice.

Most of the meshes were sculpted with a texture which is very friendly if you decide to paint it and then age it using a rag technique(spray paint on a rag and wipe) or black washing to paint the crevices. You will have to apply a primer beforehand though.

The gems were printed with transparent PETG, the profile has PLA selected because not many have it, change accordingly. Instructions below.

Print all the pieces. It is oriented a bit strange and slowed down to ensure you get good quality. If your filament is dried (mine wasnt) the supports will snap away very cleanly.

There are pegs to make sure the leaves are aligned properly. Use the images to get an idea how they are oriented. 

You can not change it around though, because the front piece fits exactly into the first leaf.

A drop of glue in the back of the gem, and secure it to the front filigree. The back gem kinda clicked into place and I did not apply any glue