Lea Stein (born 1931) is a French lady who makes jewelry and accessories from cellulose acetate (also called rhodoite). She and her husband developed a process in which several very thin layers of cellulose acetate are laminated to form a slab of multicolored plastic. This slice is then baked for a long time. After cooling, the multicolored plastic is cut into shapes. The whole process can up to 6 months require.
Lea Stein often incorporated different fabrics (such as lace) into her plastic. This creates beautiful patterns in her jewelry.

Lea Stein's jewelry can be divided into two periods: vintage (1969 to 1981) and contemporary (1991 to present). Each brooch has a v-shaped clasp that reads 'Lea Stein Paris'.