ABSTRACTThe electrical resistivity of 60 pyrite, 31 chalcopyrite, 42 pyrrhotite, 8 arsenopyrite and löllingite, 6 cobaltite, 15 galena, 13 zincblende, 26 haematite, 46 magnetite, 16 various manganese minerals, 23 complex ores and 7 graphitic shale samples (mostly from Swedish localities) was measured by the four point method. The method and the precautions needed in its application are briefly discussed. The results are presented in the form of a table which also gives other relevant data on the samples (e.g. percentage of ore in a given sample). The results are believed to be of interest to geophysicists engaged in prospecting for ore by electrical methods.The following can be mentioned among the main conclusions. The electrical resistivity of ore samples varies “locally” on a single sample often by factors of 10–100 but usually within about ± 30 and it often varies by much greater amounts (factors of 100–10000) from one sample to another. The possible causes of such variation are mentioned. The resistivity of pyrite, haematite and magnetite ore samples does not show any significant correlation with the ore content for the samples investigated. There is furthermore no correlation between the standard deviation of the resistivity on a single sample on the one hand and sample resistivity or ore content on the other hand. In the case of chalcopyrite and pyrrhotite the observations suggested the following relations:For chalcopyrite:log10(resistivity in ohmcm) = (6.2±4.2)/(vol. CuFeS2) – (I‐39 ± o.38)For pyrrhotite:log10(resistivity in ohmcm) = (73 ± 19) / (vol. FeS) – (3.26 ± o.31)The paper concludes by giving the approximate limits within which the electrical resistivity of the various ores investigated appreas to lie. The feasibility of detecting these ores by electrical operations i
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