An attempt was made to modify the band gap of CdS (approximately 2.4 eV) by preparing a mixed lattice with a low-band-gap material, PbS (0.3 eV), giving a new set of materials, CdxPb1-xS. Band gaps as low as approximately 1.9 eV were achieved with increasing x. The preparation of CdxPb1-xS was carried out by chemical-bath deposition. Structural characterization studies using X-ray diffraction (XRD), energy dispersion analysis by X-rays (EDAX), and optical microscopy were performed. The optical-absorption studies used to find the band gap are also described.