Mixed Cu-Zn ferrites (for x = 0.66 to 0.99) are prepared by the double sintering ceramic method. Locally available low cost Fe2O3 with 0.5wt% of Si additive is used for this purpose which reduced the process price markedly and improves the properties of the ferrite produced. The chemical phase analysis carried out by X-ray powder diffraction method confirms the major phase of Cu-Zn ferrite structure. Lattice parameters, X-ray density and mass density along with porosity have been investigated to study the effect of composition. Lattice parameters shows a decreasing trend with increasing Cu content, x. whereas, both X-ray density and mass density increases with increasing x, which in turn decreases the porosity due to successive presence of Si in Fe2O3. This decrease in porosity along with chemical homogeneities, distribution of phases and grain formation were also observed from Scanning electron micrographs at different magnifications.