1400 years ago Arabs burned wood for fire however they didn't know about stones that burn.
What is Coal?Coal is an organic sedimentary rock that forms from the accumulation and preservation of plant materials, usually in a swamp environment. Coal is a combustible rock and, along with oil and natural gas, it is one of the three most important fossil fuels. Coal has a wide range of uses; the most important use is for the generation of electricity.
"Coal is a combustible rock" however it was not known to Arabs 1400 years ago. But combustible rocks is portrayed in the Quran.
٢٤ فَإِنْ لَمْ تَفْعَلُوا وَلَنْ تَفْعَلُوا فَاتَّقُوا النَّارَ الَّتِي وَقُودُهَا النَّاسُ وَالْحِجَارَةُ ۖ أُعِدَّتْ لِلْكَافِرِينَ
Stones that are fuel for fire, which means they are combustible stone. Today we know that coal is combustible stone.
How could an illiterate man who lived 1400 years ago have known about stones that burn?
The Quran (Koran, the book of Islam) contains scientific knowledge that could not have been known 1400 years ago. It ranges from basic arithmetics to the most advanced topics in astrophysics. You are invited to go through those miracles and judge for yourself.