Shaping is an operation that is performed on all types of glass: sodocalcic (common glass that is sensitive to thermal shocks), borosilicate (resistant to thermal shocks) and crystal (clear and malleable). At Lalique, in addition to removing the last traces of impurities, polishing allows for the alternation of opaque and transparent surfaces. The matt (satin) appearance of the crystal is obtained by depolishing. This can be done chemically (immersion in a hydrochloric acid bath), or mechanically by projecting an abrasive material such as corundum (aluminium oxide), which is more precise than sand, or manually, using a cutting wheel.