"Coronene (also known as superbenzene) is a polycyclic aromatic hydrocarbon (PAH) comprising six 
peri-fused benzene rings.[1] Its chemical formula is C24H12. It is a yellow material that dissolves in such solvents as benzene, toluene, and dichloromethane. Its solutions emit blue light fluorescence under UV light. Its emission spectrum is not symmetrical with its excitation spectrum and varies in the number of bands and their relative intensities depending on the solvent. It has been used as a solvent probe, similar to pyrene."
"It occurs naturally as the mineral carpathite, which is characterized by flakes of pure coronene embedded in sedimentary rock. This mineral may result from ancient hydrothermal vent activity."
"Coronene is produced in the petroleum refining process of hydrocracking, where it can dimerize to a fifteen ring PAH, trivially named "dicoronylene" (formally named benzo[10,11]phenanthro[2',3',4',5',6':4,5,6,7]chryseno[1,2,3-bc]coronene or benzo[1,2,3-bc:4,5,6-b'c']dicoronene). Coronene has been seen on the surface of Titan[citation needed] (Saturn's moon). It can cause DNA damage in mammals."