I saw a "rings" render in another gallery that had a very similar flavor to these, which I thought looked terrific, so I decided to give it a whirl in TurboCAD. Getting the crisscrossing recessed path to follow both curves proved challenging but I was able to come up with an interesting way to get there. If I can remember how I got there in a day or two, maybe I will create a video. Rendered with LightWorks. Tweaked just a bit in Photoshop (added unsharp mask and adjusted the levels a bit - increase contrast). I hope that you like it.