The Book of Menstruation (Kitab Al-Haid)
Muslim :: Book 3 : Hadith 707
Ibn Abbas reported: The Messenger of Allah (may peace be upon him) happened to pass by a goat thrown (away) which had been in fact given to the freed slave-girl of Maimuna as charity. Upon this the Messenger of Allah (way peace he upon him) said: Why did they not get its skin? They had better tan it and make use of it.