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At the Canadian Malartic deposit, gold mainly occurs as fine inclusions in 1 μm to 1 mm pyrite grains hosted in altered metagreywacke. Previous time-domain induced polarization surveys conducted over this deposit have, however, failed to delineate known areas of pyrite alteration in the metasedimentary host rocks. To define the petrophysical footprint of the gold mineralization using an alternative approach, spectral induced polarization (SIP) measurements were conducted both on drill core samples in the laboratory and in situ, at a key outcrop zone. Three groups of SIP spectra are identified and interpreted using Mineral Liberation Analysis of polished thin sections and by performing Bayesian inference of SIP parameters using a Debye decomposition model. Values of Debye mean relaxation time (τ¯) and total chargeability (Σm) are used to characterize the respective SIP signatures of ilmenite-rich mudstones …