Jacquard Pre-Reduced IndigoLuscious indigo color in an easy to use form! The blue so vibrant it has its own place on a rainbow's spectrum. Natural indigo requires a chemical reduction of sodium hydrosulfite and lye to create a working dye bath. The process can be very involved, dangerous, and time consuming. As an alternative, Jacquard has developed a pre-Reduced Indigo. It still requires sodium hydrosulfite, but the lye is replaced by soda ash. It only takes 10 minutes to prepare and you get the same colorful result as regular indigo.