Various metal types tested for telluric current signal acquisition. Conductivity tests for copper and aluminium dipole electrodes.
In-situ electrode experiments. Electrode placement in relation to magnetic orientations on site proved important factors for signal acquisition as well as conditions of the soil. In particular precipitation or damp soil assisted in conductivity. Darker humus-rich soils are better conductors than sand and quartz based sediments.
Three component casting comparison tests. Various mixes and mix ratios were tested for their conductivity to bridge between the ground and the electrode. Materials included various aluminium phyllosilicate clays as well as portland cement mixed the conductive graphite powder. For the final setup employed a Greek Aluminium Phyllosilicate clay, mined on the island of Milos and refined in the Netherlands for North Sea oil and gas exploration. The Milos clay was repatriated to Greek soil for the Agora Circuit installation.
Hydrated aluminum phyllosilicate clay resistivity comparison test. Aluminium Phyllosilicate clay, aka Bentonite, is a naturally occurring clay comprised of weathered volcanic ash, with exceptional electrical properties. It sustains low grounding resistance with minimal fluctuations over extended periods when hydrated due to the card-house molecule structure it obtains when wet. Bentonite becomes electrolytic when ionized by water.