After blowing and shaping his piece, the master glassmaker adds, if necessary, the ancillary elements made by another glassmaker: a stem for glasses or a handle for vases. The object is separated from the cane with a sharp blow and then carefully transported into the annealing arch where it will slowly cool. In this type of furnace, the temperature gradually drops from 806°F (430°C) to room temperature. Lalique reserves the mouth-blown technique for round crystal objects (glasses, vases, cups, etc.). It is the lead oxide (24% minimum and 30% for the upper crystal) that gives the crystal its malleability and brilliance.