Step 1: Cut a Piece Out
The shell is slow to cut but it does cut well. Don’t force it and where a dust mask.
Be careful and work within your experience.
Step 2: Refine the Shape
At this point you can drill a hole in the pendant and make a jump ring or make a setting for it.
Keep that dust mask on.
Step 3: Make the Backing
After the strip is cut out, hammer it flat with a non-metal hammer. Cut the strip to length. Use a drill bit and locking pliers to roll the edges over.
Find something round that matches the curve of the cut piece of shell. I use a plastic cup. Roll the metal strip over the cup to make it consistent with the shell. As you go check the shell against the strip.
At this point you can bevel the edges and glue the shell to the backing or you can add sides to the backing. I used an epoxy putty on one of the pendants because the shell hand a compound curves (curves in more then one direction). That filled out voids between the shell and the backing for a secure bond.
If you go the putty route, file off any excess.
Step 4: Solder
To add sides, cut a couple more strips of metal and solder them to the sides of the backing. Use diagonal cutting pliers to cut away the excess before you grind the edges flat.
Drill a hole where the loop is going to be and use a round file to expand the hole.
I'm using silver plumbing solder on steel so won't apper seamless.
Step 5: Finish
The other pendants were brushed with a scouring pad on my drill press. I also painted the epoxy putty with a black paint pen.