This is a beautiful bird-shaped brooch pin by Line Vautrin, made of off-white resin and adorned with blue-colored mirrored glass. The artist created the unique Talosel technique, which involved using cellulose acetate that was fractured into small splinters and molded with heat. The intricate process of making Talosel jewelry included stages such as creating the mirrors, tinting them, molding the Talosel, and embedding smaller mirror fragments into it.
 
Note: Reference: This specific bird shape was also used to create the very famous "Miroir aux Alouettes" pictured in "Line Vautrin - Miroirs" by Patrick Mauriès, Galerie Chastel Marechal Editions - Copyright 2004 on page 32.