X-ray fluorescence spectrometry has been used for elemental analysis of the glazes of Chinese porcelains of the Qing, Republic, and Modern periods. This article summarizes work published in detail elsewhere. Four criteria were established to distinguish pieces made after World War II from those made before: for those with underglaze-blue decoration, the manganese/cobalt ratio was different; the relative intensity of rubidium, strontium, zirconium, niobium, and potassium showed variations; the zinc/rubidium ratio was different; the intensity ratio of barium K-alpha radiation to that of incoherently scattered gamma radiation at 59.57 keV showed differences. Porcelains made in Jingdezhen could also be distinguished from those made in other places. -- AATA