The structural and opto-electronic properties of solution grown CuxS thin films for window coatings and the precipitate used for screen printing of CuxS thick films for solar cell applications are reported. X-ray diffraction studies of the films and the precipitate showed that as-deposited films are amorphous in nature and the precipitate belongs to x = 1. X-ray photoelectron spectroscopy studies of the films indicated that they also belong to x =1. Annealing of the films and the precipitate in air increased the electrical conductivity by a few orders of magnitude, but the conductivity decreased rapidly above 220 degrees C. This is attributed to the decomposition of CuS at about 220 degrees C. Above the decomposition temperature both the film and the precipitate annealed in air contained species such as CuSO4 and Cu3SO4(OH)(4). Scanning calorimetric analysis of the precipitate indicated the phase changes observed in XRD studies.