Sahih Bukhari

Narrated Abu Huraira:Allah's Messenger (ﷺ) said, ""Soon the river ""Euphrates"" will disclose the treasure (the mountain) of gold, so whoever will be present at that time should not take anything of it."" Al-A'raj narrated from Abu Huraira that the Prophet (ﷺ) said the same but he said, ""It (Euphrates) will uncover a mountain of gold (under it)