This kit contains everything you need to dye with indigo crystals (aka pre-reduced or synthetic indigo). Alum is included as a mordant for wool or silk; mordanting is not required for cotton and bast fibers.
2oz Indigo Crystals
4oz Alum (Potassium aluminum sulfate)
4oz Soda Ash (Sodium carbonate)
4oz Thiox (Thiourea dioxide)
2oz Glauber’s Salt (Sodium sulfate)
1oz Chalk (Calcium carbonate)