  It has been recently shown that precipitation bands characteristic of
Liesegang patterns emerge from spinodal decomposition of reaction products in
the wake of moving reaction fronts. This mechanism explains the geometric
sequence of band positions x_n ~ Q(1+p)^n and, furthermore, it yields a spacing
coefficient, p, that is in agreement with the experimentally observed
Matalon-Packter law. Here I examine the assumptions underlying this theory and
discuss the choice of input parameters that leads to experimentally observable
patterns. I also show that the so called width law relating the position and
the width of the bands w_n ~ x_n follows naturally from this theory.
