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Six very low frequency electromagnetic (VLF-EM) lines were surveyed across the expected strike of a lead sulphide lode in a mine in the Abakaliki lead/zinc field of Nigeria. The aim of the survey was to investigate the lateral extension of the lode and establish the potential of this tool for mapping sulphide deposits in an area underlain principally by shales. VLF-EM field values were filtered using Fraser filter and the results plotted directly over the survey lines. The plots were examined for significant anomalies that could be related to the lode. About 40 m length of the lode was successfully mapped by this simple, inexpensive tool. The anomalies strike NW–SE following the strike of one of the predominant set of faults. A depth of 10 m and a dip of 90° were calculated for the conductor. [Copyright &y& Elsevier]