From Sahih Muslim (Hadith 7272):
Abu Huraira reported Allah's Messenger (ﷺ) 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)
Reference: Muslim 7272