Sahih Bukhari, Chapter: Lost Things Picked up by Someone (Luqaata)

A man asked Allah's Apostle (SAW) about the Luqata. He said, "Make public announcement of it for one year, then remember the description of its container and the string it is tied with, utilize the money, and if its owner comes back after that, give it to him." The people asked, "O Allah's Apostle (SAW)! What about a lost sheep?" Allah's Apostle (SAW) said, "Take it, for it is for you, for your brother, or for the wolf." The man asked, "O Allah's Apostle (SAW)! What about a lost camel?" Allah's Apostle (SAW) got angry and his cheeks or face became red, and said, "You have no concern with it as it has its feet, and its water-container, till its owner finds it."