I am in the minority but I like roll-stoppers. I generally do not carry a pen in a shirt pocket so the only real purpose that I get from clips is to stop the pen from rolling and adornment. Metal clay roll stoppers give you an opportunity to add some uniqueness to your pen. That having been said, can you tell us more about your stoppers? Type of clay? I do not have a kiln so I only buy clays that can be torch fired. I do a preliminary shaping of the clay, dry the shaped clay in a toaster oven, do some sanding and clean up of the dried clay, fire with a MAPP torch for 7 minutes, quench, and polish the pieces. My clay pieces are usually somewhat crude but true clay artists can do some fantastic stuff with them.
Your roll stoppers are creative and I like where you are going but based on your photos they do not appear to have been fired properly.
Here is a post of a dolphin stopper that I did:
I made a metal clay dolphin roll stopper for my recent completed kitless fountain pen. Clay shaped and ready for firing Firing Finished pen
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