Non-destructive and non-invasive methodology for the in situ identification of Mexican yellow lake pigments

•Non-contact colorimetry yielded three groups of yellow lakes.•UV and false color UV imaging further divided the lakes into four groups.•Principal component analysis of the FORS spectra differentiated the dyestuffs used.•Raman spectroscopy allowed a final refining step.•A flowchart was proposed for the precise identification of the yellow lakes.