Musnad Ahmad 28:207

Ya'la narrated to us, Muhammad ibn Ishaq narrated to us, from 'Amr ibn Shu'ayb, from his father, from his grandfather, who said: I heard a man from Muzaynah asking the Messenger of Allah, peace and blessings of Allah be upon him. He said: "O Messenger of Allah, I have come to ask you about a stray camel?" He said: "It has its footwear and its water-skin; it eats the trees and drinks the water, so leave it until its seeker comes to it." He said: "What about a stray sheep?" He said: "It is for you, or for your brother, or for the wolf; gather it until its seeker comes to it." He said: "What about the *harisah* (stolen sheep) found in its grazing lands?" He said: "For it is its price twice over, and a disciplinary beating. And what is taken from its resting place, in it is the cutting [of the hand], if what is taken of that reaches the price of a shield." He said: "O Messenger of Allah, what about fruits, and what is taken of them while they are in their coverings?" He said: "Whoever takes with his mouth, and does not take [it away] in his garment, there is nothing upon him. And whoever carries [it away], upon him is its price twice over, and a beating, and a disciplinary punishment. And what is taken from its drying floors, in it is the cutting, if what is taken of that reaches the price of a shield." He said: "O Messenger of Allah, what about a lost item we find on a frequented road?" He said: "Make it known for a year; if its seeker is found, then return it to him, and if not, then it is yours." He said: "What about what is found in ancient ruins?" He said: "In it, and in buried treasure (*rikaz*), is one-fifth."