Abstract <p>A comprehensive study of graphite from the Pestpaksha deposit (Lapland Granulite Belt, Kola Region) has been conducted, including Raman-based temperature determination and carbon isotopic characterization. Also studied were C and O isotopic compositions of carbonates from the rocks adjacent to graphite ores. The structural control of the graphite mineralization indicates that it was crystallized from the fluid phase. The crystallization of graphite was found to have taken place at a temperature of about 600°C at the retrograde stage of the metamorphic event. Broad variations in carbon isotopic composition (δ¹³C_V-PDB from –18.5‰ to –29.0‰) can be explained either by the mechanism of Rayleigh depletion of C–O–H fluid with a high CO₂ fraction in a system closed relative to this fluid, or by the mixing of carbon from two isotopically contrasting sources. These sources may be the ¹³C-poor methane-bearing fluids produced during degassing of metamorphic rocks and the carbonates anomalously enriched in ¹³C (δ¹³C_V-PDB ~ +14‰) observed in this study, which are similar in isotopic characteristics to carbonate rocks of the Lomagundi-Jatuli event. In the Rayleigh depletion model, these specific rocks are considered to be the product of crystallization of the residual fluid. Regardless of the formation model adopted, the available evidence suggests that Pestpaksha graphite inherited its isotopic signature (δ¹³C_V-PDB of ca. –25‰) from hydrocarbons and is most likely derived from a metamorphic event.</p>