Abstract: An electromagnetic measuring probe has a pole-piece composed of a magnetic material of high magnetic permeability. The pole-piece has a front face. A recess is machined into the front face and extends into the pole-piece. A pin is positioned within said recess. The pin is composed of hard metal which has a low magnetic permeability in comparison to the material of the pole-piece. The pin has an external front face which comprises the crowned contact surface of the measuring probe.