When a child comes of age, they go through the ceremony of colour. Where their soul pigment is revealed to them.
This is done by the Shaman, where they blow bone/white pigment into the light onto the child, and the colour then switches once it reaches the light and the child's aura. The child then climbs up and mark the pillar with their soul circle to make their soul a part of the tribe, connecting them to the rest of the people.
Did this to practice my illustrative skills, and to learn UE5 in my workflow.