Leviticus 13:20-24

and the priest shall look, and behold, if it appears to be deeper than the skin, and the hair on it has turned white, then the priest shall pronounce him unclean; it is the infection of leprosy, it has broken out in the boil.

But if the priest looks at it, and behold, there are no white hairs in it and it is not deeper than the skin and is faded, then the priest shall isolate him for seven days;

and if it spreads farther on the skin, then the priest shall pronounce him unclean; it is an infection.

But if the bright spot remains in its place and does not spread, it is only the scar of the boil; and the priest shall pronounce him clean.

“Or if the body sustains in its skin a burn by fire, and the raw flesh of the burn becomes a bright spot, reddish-white, or white,