My daughter wanted two necklaces, one for her, and one for her best friend, that represent Yin and Yang symbol when you assemble them. I was not able to find what I wanted, so I made it :) Each part can be printed alone, or you can print both, to make the Yin and Yang symbol when assembled together. Very quick to print ( about 6 minutes on my GeeeTech i3) You will also need: 2 rings to attach on the cord 2x 70 cm of cord (for kids, 10-20cm more for an adult)
Download from thingiverse