An ancient form of casting, Lalique's cire perdue method greatly differed from his commercial moulded glass production. Covered in plaster, an original wax model was left to dry; the model was then warmed, and the melted wax was permitted to run out, leaving behind a mould into which molten glass could be poured or blown. Once the glass had reached a cooling point, the plaster was removed: thus, the mould was destroyed, creating a unique piece of glass. Two distinctive features of glass produced by the cire perdue technique are its rough surface texture, which remains unpolished, and the absence of mould lines.