Soil organic carbon (SOC) in the reclaimed coal mined soils is a mixture of carbon (C) from the humified organic matter (OM) and coal residues incorporated during mining and reclamation processes. Thus, quantification of soil organic carbon sequestration rates also requires quantification of coal C in reclaimed minesoils. A method for determination of coal C concentration in reclaimed minesoils is presented. Differentiation of coal C from soil organic C is based on solubility of soil organic C and oxidative stability of coal. The method involves chemical pretreatments, followed by thermal oxidation at low temperatures remove inorganic and organic C. Coal C is quantified by dry combustion method in CN elemental analyzer. Analysis of coal, coal-free soil and coal and soil mixtures revealed that coal C was highly resistant to both chemical treatment and thermal oxidation for the experimental conditions tested, with losses of C ranging from 0 to 5% of coal C, while OM carbon removed ranged from 94 to 98% of SOC. Analysis of soil samples from the reclaimed mined sites of Southeastern Ohio indicated that variation of coal C concentrations in the reclaimed mined sites was wide (0 to 67% of SOC). The highest concentrations were detected in the sub soil. δ¹³ C analysis revealed that the remaining C in soil and coal mixtures and minesoils was more isotopically similar to coal C, confirming that soil organic C was removed by the chemi-thermal method.