Leviticus 13:54-56

⁵⁴then he will command them to wash the item in which the mildew was found, and he must isolate it for seven more days.

⁵⁵Then the priest will examine the item after the mildewed item was washed. If the mildew has not changed its color, even though it has not spread, it is unclean. You must burn the item, no matter where the mildew has contaminated it.

⁵⁶If the priest examines the item, and if the mildew has faded after it was washed, then he must tear out the contaminated part from the garment or from the leather, or from the woven or knitted material.