Is the hand that handles impurity when cleaning with water (kur) automatically purified after the roughness is gone?

The hand is considered pure if no trace of impurity, neither color nor smell, remains on it after istinja' (cleaning oneself after relieving oneself). However, it is preferable to wash it with earth or soap to remove any unpleasantness. In Sahih Muslim, Maymuna (may Allah be pleased with her) described the Prophet's (peace and blessings of Allah be upon him) istinja' by saying: "Then he struck his hand on the ground and rubbed it vigorously."

However, if a trace of impurity remains on the hand after istinja', it must be washed until it becomes pure. The smell is excused if its removal is impossible.