Reprint of “Petrological and organic geochemical properties of lignite from the Kolubara and Kostolac basins, Serbia: Implication on Grindability Index”

Analysis of biomarkers indicated that the negative impact of all types of xylite-rich coal from the Kolubara on HGI can be related to the higher proportion of angiosperms, abundance of mid-chain n-alkanes and sesquiterpenoids, aromatization of non-hopanoid triterpenoids and hopanoids, and intense degradation of wood tissues in a more oxic environment. The positive impact of matrix coal on HGI in the Kolubara samples can be attributed to elevated content of non-aromatic hopanoids and low amounts of aromatic non-hopanoid triterpenoids and sesquiterpenoids, which seems to hinder the grindability properties.