Leviticus 13:51-52
51 On the seventh day he is to examine it, and if the mildew has spread in the clothing, or the woven or knitted material, or the leather, whatever its use, it is a destructive mildew; the article is unclean.
52 He must burn up the clothing, or the woven or knitted material of wool or linen, or any leather article that has the contamination in it, because the mildew is destructive; the article must be burned up.