I like the differential focus and the high-key treatment, works well since there isn't any colour in the ring and it also creates a 'purity' mood for the image.
Note that almost black line reflected on the band, created by the gap in your light tent for the camera no doubt, how it gives the metal something more. Thats what I was on about in the other ring example.
BTW are you going to change your moniker to LOTR - Lady Of The Rings?
Hmmm, might be an idea for your client too!
Would certainly be a challenge to facilitate that idea in PS.
Nice work, did I say that already?
Les