Seashell bottle bottom mold. Simply cut off the bottom of a large bottle, add it to the prepared mold and fuse. This guy is sized to fit 1.5L wine bottles, that’s the big bottles. Requires Kiln Wash
Instructions and firing schedules are included with the mold.
Tutorials featuring bottle bottom molds:
Using Bottle Bottom Molds
Fusing in pilot holes to make drilling easier
Fusing Brass loops in bottle bottoms
Man in the Moon with Stars