Resistivity of copper and steel in 20 ℃ respectively is 17.24 x 10-6 (Ω mm) and 138 x 10-6 (Ω mm). If the conductivity of the copper is 100%, the conductivity of the standard 1020 steel is only 10.8%, the conductivity of the galvanized steel is only 8.6%, so the conductivity of the copper is about 10 times of steel.
Pure copper ground rod is the best ground rod, can use H90, H70, H68, a variety of specifications H65 and H62 brass to make ground rod body, suitable for the use of lightning protection conductive to demand higher occasion.