  We describe the construction and characterisation of a nano-oscillator formed
by a Paul trap. The frequency and temperature stability of the nano-oscillator
was measured over several days allowing us to identify the major sources of
trap and environmental fluctuations. We measure an overall frequency stability
of 2 ppm/hr and a temperature stability of more than 5 hours via the Allan
deviation. Importantly, we find that the charge on the nanoscillator is stable
over a timescale of at least two weeks and that the mass of the oscillator, can
be measured with a 3 % uncertainty. This allows us to distinguish between the
trapping of a single nanosphere and a nano-dumbbell formed by a cluster of two
nanospheres.
