Summary By x-rays analysis the identification of the mineral constituents in a sample of milkstone was determined. Results obtained from the diffraction of x-rays by milk powder show conclusively that lactose does not exist in a crystalline form in fresh milk powder. The very onset of lactose crystallization in milk powder was shown by the diffraction patterns obtained. Also a tendency for a change of nite spacing of the diffracting group in milk protein due to different processing methods has been noted. Spray powders were found to have a slightly greater d1 unit spacing than the roller powders.