Resin and metal bezels can create wonderful little worlds.

Most suppliers have this type of decorative bezel available to fill with your treasures. You can fill with many things like color and texture and of course 3-d objects. Used plain like this they are a good base.

I noticed this open back bezel in my stash and it is a close, though slightly loose fit over the bezel.

This seems to me to add a porthole look to the piece. Like a decorative frame.

Of the many products we can use under Ice Resin this Shattered Fire Opal is one I adore. The color is like a fine broad flash opal when sealed in resin. I applied some of the medium and filled the bezel. Then allowed it to dry while I was warming the Ice resin to slightly above room temperature about 85 degrees. I mixed the resin in the prescribed manner and set it to rest for 10 minutes on a warm spot. This rest allows all the bubbles to dissipate.

Next I looked for a subject to put inside on top of the resin. This fellow was a possible fit.

As is this tumbling baby. Both of these and hundreds more are available through my Etsy shop.
 https://www.etsy.com/shop/oscarcrow

I chose this cherub or angel. The brass bezel was glued down to the decorative one with E-6000 and allowed to cure for five minutes. When that was secure I poured the resin and  filled the bezel to secure the cherub and cover the opal glitter in the back. I put this in a covered plastic food box and set it in a warm place on a cable TV box to cure. Two days later I trimmed some small leakage and now it is ready to add the finishing touches, a necklace and a pearl drop or a crystal.

To me this is a bit like making a high rise cameo. It is easy and by selecting a single focal point we have a strong design.