Most important of all is the choice of mordant. Mordants are chemicals that help improve the depth of color and the fastness of the dye. The most commonly used mordants are the metallic salts of alum, chrome, iron, and tin. The chosen mordant and the way it is used depends on the dyestuff, the fiber being dyed, and on the color desired. She frequently obtains eight or more harmonizing colors from one dye bath by dying several batches of wool, each previously prepared with a different mordant.
Tin is caustic to the skin.
You must use common sense and dump both the mordant and dye bath where no pets or children can get to it. To share her knowledge of how to use natural dyes, Carol Leigh offers two workshops a year at her studio. Carol Leigh's Specialties also supplies mordants, imported dyestuffs, books on natural dyeing, handspun yarns, handwoven fabrics and garments, custom-made textiles, offers classes in spinning and weaving, and markets a patented triangular loom. And to underscore the remarkable sense of human continuity inherent in natural dyeing, Carol Leigh still uses those tinctorial berries to color her wool. Copyright Phyllis Rossiter Modeland.