لطائف قرآنية 23

by Stuart E. Nevins, M.S
Accumulated, compacted and altered plants form a sedimentary rock called coal.
http://www.icr.org/article/origin-coal/

of vegetation that grew as long as 400 million years ago. It is often referred to as "buried sunshine," because the plants which formed coal captured energy from the sun through photosynthesis to create the compounds that make up plant tissues. The most important element in the plant material is carbon, which gives coal most of its energy
http://www.ket.org/trips/coal/agsmm/agsmmhow.html