  By modeling a colloidal suspension at rest as a solid, a new expression for
the linear elastic modulus is obtained. This estimate is valid for a yield
stress colloidal suspension submitted to a small strain. Interestingly, it is
also possible to construct an hypothesis allowing one to recover the
high-frequency modulus classically found by means of a classical ?fluid
approach'. However, in most of the situations, the moduli obtained by the two
approaches are different.
