I've had to make this halo for a client recently and here I'll attempt to show some of the processes and techniques that I've used to make it all happen!
Firstly I needed to make a master shape focusing on half of the halo, which later I will make a silicone mould of and eventually cast 2 halves and join them into one seamless piece. I started by using auto cad to draw up 3 simple circles at around 200mm in diameter and 16mm wide, these had to be of different widths though, the wider on the bottom (18mm) and the narrower on the top (3mm) creating and incremented curve if seen in section. These cad drawings were eventually used to laser cut the circles in 2mm acrylic which allowed me to physically stack them on top of each other. The increments were then filled with car body filler, then sanded the filler down gently while trying to avoid sanding much of the acrylic, making sure I retain the accurate circle shape. Once filled and primed I was ready to make a silicone mould. Then casted 2 halves, joined them, filled the seam and primed and sanded the surface until smooth like a babies bum, ready for the final gold colour coat of paint. This was made in 2.5 days through an impulsive and intuitive approach, through blending simple techniques from various backgrounds.