Chiffon is a lightweight sheer fabric originally produced with silk yarns, however new processes and new technology has developed chiffon is now produced with nylon and polyester yarns. This is a cheaper lightweight fabric if produced with synthetic yarns, the advantage of synthetic over silk is the durability aspect so the fabric will naturally last longer than a silk chiffon.
Looking closely at the chiffon you will see similar construction like a net, it is a fine material with more of a spaced weaving method. Crepe chiffon has more of a texture as the two yarns are twisted both the warp and weft in an order creating a crinkled effect. This adds to the texture and characteristics of the fabric so if you are using it for any project it will add a difference to the fabric and lift it.
