6. Spruing. Once the wax copy looks just like the original artwork, it is "sprued" with a treelike structure of wax that will eventually provide paths for molten bronze to flow, while allowing air to escape. The carefully-planned spruing usually begins at the top with a wax "cup," which is attached by wax cylinders to various points on the wax copy.

7. Slurry. A "sprued" wax copy is dipped into a slurry of liquid silica, then into a sand-like "stucco", or dry crystalline silica of a controlled grain size. The slurry and grit combination is called "ceramic shell" mold material, although it is not literally made of ceramic. This shell is allowed to dry, and the process is repeated until a half-inch thick or thicker dries coating covers the entire piece. The bigger the piece, the thicker the shell needs to be. Only the inside of the cup is not coated, and the cup's flat top serves as the base upon which the piece stands during this process.

8. Burnout. The ceramic shell-coated piece is placed cup-down in a kiln, whose heat hardens the silica coatings into a shell, and the wax melts and runs out. The melted wax can be recovered and reused, although often it is simply combusted by the burnout process. Now all that remains of the original artwork is the negative space, formerly occupied by the wax, inside the hardened ceramic shell. The feeder and vent tubes and cup are now hollow, also.

9.Testing. The ceramic shell is allowed to cool, then is tested to see if water will flow through the feeder and vent tubes as necessary. Cracks or leaks can be patched with thick refractory paste. To test the thickness, holes can be drilled into the shell, then patched.

10. Pouring. The shell is reheated in the kiln to harden the patches, then placed cup-upwards into a tub filled with sand. Bronze is melted in a crucible in a furnace, then poured carefully into the shell. If the shell were not hot, the temperature difference would shatter it. The bronze-filled shells are allowed to cool.