One ounce of all-natural blue fabric dye made from the fruit of the Cape Jasmine flower. One ounce will dye up to a pound of wool or silk to a gorgeous sky blue color. One of the only natural blue fabric dyes that doesn't require making an indigo vat. Recommended for protein fibers only (wool and silk); produces very faint colors on cotton. Shepherd Textiles Cape Jasmine Extract Natural Dye is an all-natural blue fabric dye made from the flowers of the Cape Jasmine (gardenia jasminoides). It produces gorgeous blue-greens on natural fibers like wool and silk.