• 1 cup vinegar
• copper scouring pad – if new, pound the pad to crack the coating that keeps it from oxidizing in the store

Soak for several weeks, then add:

• Alum
• Cream of Tartar

• 1 Large purple cabbage – chopped
• water to cover

Simmer until color is gone from leaves.
Add mordant and fibers. Simmer six hours. Cool overnight in dye-bath. Rinse in cold water with vinegar.