Fig. 4

The conductivity of the gypsum sample without NaCl in the casting compound a average over all three series of measurements (color-coded dashed lines) in 0.17% NaCl solution adjusted to 25 °C and b average with the outlier (series 1) removed is shown on the right. The conductivity is shown for (top) frequencies of 0.1 Hz to 100 kHz and (bottom) 1 Hz for 10 min. The shaded regions show µ ± σ (purple) and µ ± 0.5µ (blue) for comparison on the left and µ ± 0.05µ (blue) for comparison on the right