A hand tool has a handgrip attached to a ground-piercing probe, which is
manually insertable in the soil. The probe has a chamber in which at least
one inductor is positioned and connected to metal detection circuitry. The
preferred circuitry has a pulse generator applying current pulses to an
inductor for inducing eddy currents in a buried target object. After the
pulse terminates, the decaying coil voltage is sampled at different times
to detect both the presence and range of the object, as well as the type
of metal in the object. An asymmetric magnetic field pattern about the
probe is aligned with a direction pointing indicium on the handgrip and
provides directional sensitivity. The coil voltage samples are applied to
signaling circuitry, which provides an audible signal which is a series of
bursts of an audio tone. The pitch of the audio tone signals the presence,
range and bearing of the buried metal object, while the pulse rate of the
bursts signals the metal type.