(Ar-Rahman) 55 : 37
فَإِذَا انْشَقَّتِ السَّمَاءُ فَكَانَتْ وَرْدَةً كَالدِّهَانِ
Then the sky will get ascender and will become melted just like ointment in red colour.
The sky seen as blue color today will be melted on Doomsday and will become just like ointment in rose color. See explanation 21: 104; 69: 16; and 70: 8.