Yahya related to me from Malik that Rabia ibn Abi Abd ar-Rahman
heard Anas ibn Malik say, "The Messenger of Allah, may Allah bless him
and grant him peace, was not excessively tall or short. He was not
very pallid nor dark. He did not have curly hair or lank hair. Allah
commissioned him at the age of forty. He stayed in Makka ten years and
at Madina for ten years and Allah the Mighty, the Majestic made him
die when he was sixty. There were not twenty white hairs in his hair
or beard, may Allah bless him and grant him peace."
Muwatta Malik Book 49, Hadith 1