...and rhodium plating. (I think.. not my area)
Is it yellow or white gold? - curiosity..
White. All white gold is now rhodium plated. You know, to make it 'extra' white. :er:
Let me start by saying I have no business giving you criticism AND I know you didn't ask for it but I might learn something from your reply.
Criticism is always welcome.
I'm unsure of the composition. I don't know if it's a common layout for jewelry, or any product really, but the bordered ring on the right strikes me as odd. Also the lighting makes it look like it's leaning ever so slightly to the right. Also, I think the shadow in the 3rd image on the bottom could use some dodging..
I don't think composition is that important for product portfolio images.
I don't know if it's common either.

I am going for "my take" and trying to be a little different. As far as the lean, yeah, it is leaning slightly right, to compensate for my imperfect wax carcing, making the ring uneven to the left. :meh: I hate seeing flaws when the job is done. When you spend a lot of hours on a piece, you start to not see things, if that makes sense.

I think you are right about the last shadow, I'll knock that back a bit. As for the border, I thought I had black border going around the whole image, half the thickness of that end block. It was 2am, again, I didn't see what happened to it. I was trying to use that last block as an inset to show detail of the stone setting, in that groove. If I left the ring image the size of the others, to follow along, you couldn't see the detail. I think now I should a) fill the frame with the ring detail, and b) thin the border. maybe making it even, and all the way around the image will help.
I like the sharpness and the shallow depth of field, very pleasing to look at. You did great showcasing how beautiful the ring is (I assume you crafted it?).
Yes, it is my design, and creation. I am learning to use the tilt shift lens, and it is interesting. I learned why all y shots so far have missed focus.

On this lens you have to focus using Live View, and you have to press the depth of field preview button in to focus. I am however really happy with being able to focus across the top of a ring and blur the shank below. I can get much more in focus than with my macro lens. Problems, however, are dealing with chromatic abberation.
Customers have responded really well to my images so far, and after this one, one customer (retailer) wants to hire me to photograph his jewelery for web and print. I need to create my lighting setup first, and then find some more hours in the day. This could turn into a cool additional service to offer through my biusiness. :mrgreen:
:hug::
How you doin' with your camera? Getting better?