Narrated Hariz bin 'Uthman: That he asked 'Abdullah bin Busr (i.e. the companion of the Prophet), "Did you see the Prophet when he was old?" He said, "He had a few white hairs between the lower lip and the chin."
— Sahih Bukhari, Volume 4, Book 56: Virtues and Merits of the Prophet (pbuh) and his Companions, Hadith #746