وعنها قالت: خرج رسول الله صلى الله عليه وسلم ذات غداة، وعليه مرط مرحل من شعر أسود
One morning the Messenger of Allah (sallallahu alayhi wa sallam) went out wearing a black blanket made of a camel or sheep’s black hair with patterns of camel’s bags upon it.
Riyad as-Salihin 786, Book 4, The Book of Dress, Hadith 9. 1 min read