Electrical conductivity of different rocks and soils lays the base for electrical logging and electrical and electromagnetic (E&EM) methods that have been extensively used for near-surface, environmental, and hydrogeological investigations (e.g., Glover, 2015). It is the pioneering work of Archie (1942) that makes the quantitative assessment of porosity available and paves the way for other petrophysical parameters. Several years later, Patnode and Wyllie (1950) found that Archie's law is only suitable to "clean" samples as clayey minerals in the "dirty" ones present themselves as "conductive solids". Winsauer and McCardell (1953) ascribed the clay conductivity to its electrical double layer (EDL) for the first time. Thus the additional component Patnode and Wyllie (1950) added to Archie's law shall be called the surface conductivity. Soon after, Wyllie and Southwick (1954) discovered that the surface conductivity is not constant but differs at low and intermediate salinities, and they presented a three-resistor (TR) model to explain this non-linearity. It shall be clarified here that "cleanness" and "dirtiness" are relative terminologies that are essentially a question of the ratio between surface and pore water conductivity (i.e., the Dukhin number. cf, Shilov et al., 2001). Indeed, one can find surface conductivity even in clean glass beads (e.g., Bolève et al., 2007).Although research on the electrical conductivity of clayey rocks and soils progressed significantly in the 1950s, the following years are not always the case. Despite the fact that many models have been presented to account for this non-linear characteristic, they are argued not to comply with electrochemical theories or not coincide with measurements, and most are too complex to use (Bussian, 1983). For example, the TR model (Wyllie & Southwick, 1954) can explain measurements well, yet it is exclusive of EDL, clay minerals being treated as classic conductors. The Waxman-Smits (WS) model (Waxman & Smits, 1968), probably the most popular model, postulates that the ionic mobility decreases with the diminishing ionic concertation which is opposite to the electrochemical theory (e.g., Bockris & Reddy, 1998). The Padé approximant (PA) model (Schwartz et al., 1989) first calculates the low-salinity conductivity with surface tortuosity and the high-salinity conductivity with bulk