I made the 24 LED ring for brooch. Recently I draw a new one with Fusion 360 .

To make this brooch, you need

LED ring with 24 right-angle LEDs, inwards facing

Blinkytape controller

transparent pvc mirror fabric (This is optional, if you don't want the mirror effect can skip it)

40mm round cabochon

I print the brooch-out first, and put the round cabochon inside, then file and modify the brooch-in a little bit. Then screw in the outside part to lock the cabochon in place. Cut transparent pvc mirror fabric, put it under between the ring pcb and the brooch-in plastic. Put the ring pcb in. Add another transparent pvc mirror fabric under the ring pcb to make the mirror effect. Then cut a little of the bot piece for wire then glue them together. 

The Ring led pcb is use JST connector to connect to the blinkytape controller.