• The initial chemical composition has an effect on Raman spectra in charcoals. • This composition effect disappears in charcoals formed above 600 °C. • Raman spectra may reveal differences in the intensities of archaeological fires. Charcoal is a key archaeological artefact, providing evidence of human presence, enabling site dating and delivering information about ancient practices notably through Raman thermometry. This study explores how it can be used to investigate past anthropogenic pract