The Book Pertaining to the Turmoil and Portents of the Last Hour (Kitab Al-Fitan wa Ashrat As-Sa`ah)
Muslim :: Book 41 : Hadith 6918
Abu Huraira reported Allah's Messenger (may peace be upon him) as saying: The Last Hour would not come before the Euphrates uncovers a mountain of gold, for which people would fight. Ninety-nine out of each one hundred would die but every man amongst them would say that perhaps he would be the one who would be saved (and thus possess this gold).