The master glassblower’s steady breath allows him to create a bubble in the molten crystal mass. He must obtain a smooth surface and remove all impurities with a blowtorch or metal tongs. The glassmaker knows the final shape he wants to give to his piece. He turns his cane in a regular movement and shapes the bubble with the help of tongs. By tilting it, he lengthens its shape to a greater or lesser extent. At Lalique, the mouth-blown technique is reserved for round crystal objects (vases, bowls, etc.). It is the lead oxide (24% minimum and 30% for the upper crystal) that gives the crystal its malleability and brilliance.