Leviticus 13:52-55 New International Version (NIV)

52. He must burn the fabric, the woven or knitted material of wool or linen, or any leather article that has been spoiled; because the defiling mold is persistent, the article must be burned.

53. “But if, when the priest examines it, the mold has not spread in the fabric, the woven or knitted material, or the leather article,

54. he shall order that the spoiled article be washed. Then he is to isolate it for another seven days.

55. After the article has been washed, the priest is to examine it again, and if the mold has not changed its appearance, even though it has not spread, it is unclean. Burn it, no matter which side of the fabric has been spoiled.

Leviticus 13