Leviticus 13:4

But though the whiteness be exceedingly bright on the outer coat of the skin, if the appearance of it be not deeper than the outer coat, and the hair thereof be not turned white, but is of a dusky colour; the priest shall set apart the patient seven days.

But if the spot be clear and white in the skin of his flesh, yet the appearance of it be not deep below the skin, and its hair have not changed itself for white hair, but it is dark, then the priest shall separate him that has the spot seven days;