EDXRF analysis of Straits Chinese porcelains for zirconium and niobium using a cadmium-109 source

An annular Cd-109 source was used to induce fluorescent X-rays from 37 pieces of Straits Chinese porcelain of which four were modern pieces and the rest were produced from the nineteenth century up to the Republic period (1912-1939). Experimental data show that for zirconium and niobium infinite thickness is reached for a thickness of about 1.5 mm. A plot of the intensity of the K/sub α/1 line of Zr against that of Nb shows that all Ch'ing and Republic pieces cluster together and are quite distinct from the modern pieces, allowing easy nondestructive identification of modern fakes