At first glance, I was thinking this might be a P6m symmetry challenge. Pulled up KaleidoPaint on the tablet and tested my theory.
Indeed, it was as simple as drawing a single arc, linking the two ends of one of the 6 mirrors. I did need to tweak the control points in order for the encompassing circle to be perfect. And that was it! Sometimes it’s nice to stay simple. The artists before us certainly knew this.
The image below shows the same line repeated in different colours across the various mirrors.
A few added lines, and a black background.
A few minor variations in the arc, and the design changes completely.
Interesting Wikipedia page on the topic of overlapping circles grid, or more recently dubbed Flower of Life.
2019-01-01; Found this little tidbit on Facebook this week. Blows my mind indeed!