Beautifull !

Did you use a Resin printer for the 3D model ? I've heard that's the usual way to make 3D rings without needing supports everywhere.

Something about types of resins that vaporize/burn completely in the mold without leaving traces, for a clean mold.
Read up about it given I nearly won a resin printer recently (I ended up second place, so I won the FDM printer price instead. but it's my first printer, so I'm still very happy about it), and reading about how they're used led me to a guide on Investment Casting using 3D models made from Resins.

I had no idea you could do that with a 3D printer at the time XD