  Nuclear recoil cascades induced by Cold Dark Matter (CDM) elastic scattering
can produce the ejection of target atoms from solid surfaces. We calculate the
yield and energy distribution of these sputtered atoms in a variety of
materials. These parameters would suffer a large diurnal modulation induced by
the rotation of the Earth and its motion through the galactic halo. Schemes for
the detection of this unique CDM signature are proposed.
