The Mayo Clinic reports that sweat has no odor until it reaches the skin and mixes with bacteria. Commercially available deodorant products often contain chemicals that irritate sensitive skin. A deodorant made from crystallized alum forms a barrier, neutralizing bacteria instead of masking it like some commercial deodorants do.
You will need:
Step 1: Pour 1 cup hot water into the jar. Slowly and gradually stir in 2 ounces of alum until stops dissolving and settles at the bottom of the jar.
Step 2: Add ¼ of the solution to the dish.
Step 3: Stir 1 tablespoon of alum powder into the solution that remains in the jar. Cover the remaining solution in the jar with a clean cloth. Store the covered jar in a warm, dry area.
Step 4: Allow the dish to sit uncovered overnight. The crystals will form in it.
Step 5: Check the dish the following day. Select the largest crystal. This will serve as the seed crystal for the deodorant.
Step 6: Remove the cloth from the jar. Tie one end of the fishing line around the crystal and the other end around the ruler. The length of the line depends on the height of the jar. The line should be long enough to suspend, yet fully submerge, the crystal in the liquid. When the crystal hangs, it should not touch the sides or bottom of the jar.
Step 7: Store the jar uncovered in a warm, dry place. Check the jar every few days. If crystals begin forming on the jar sides, move the crystal and solution to a new jar so it can continue to grow. Small crystals compete with the seed crystal to absorb the alum.
Step 8: At least two weeks is required for the crystal to reach adequate size but you can allow it to grow larger if you wish. Before using the crystal, use a paper towel to wipe it and a file to smooth rough areas. Use the crystal on your underarms as you would apply deodorant.