You’ll be able to build one you like once you get your head around what you like.
The next time you look at a piece and like how it appears, pay attention to what you are really seeing. What is being reflected? Is the light moving around? How is it lit?
Visit a retail jewelry store. Find a case that really makes the pieces look good. Then figure out why they look good. How is the room lit? What color is the ceiling? Is it black with lots of small pin light sources? Is that what you’re seeing that you like?
Once you understand what you like what what is involved in getting the look, then model a little scene that produces similar lighting and interesting reflections.
Build a space that makes your renderings look good.