Casting rocks are unannealed random shapes between the sizes of grapes and baseballs. They are a low cost source of premium formula casting glass. If your casting does not need the low bubble count and uniform shape of Casting Billets, choose Casting Rocks as an economical alternative. Each container has a variety of sizes, so you can pick the size and weight you need to fit any mold.
Questions about firing schedules? When planning a firing schedule for heavier castings, please refer to our Firing Guidelines.