An EPR study on ancient and newly synthesised Egyptian blue,

Two sets of ancient roman Egyptian blue (EB) samples and one set of EB samples synthesised in our lab, were analysed by EPR spectroscopy, a technique not commonly used in this field. The spectroscopic parameters obtained were used to attempt the discrimination of the provenance and of the manufacturing techniques of the investigated samples. The results obtained show that EPR technique could be very useful for this purpose. Furthermore, the similarity of the obtained parameters between the ancient and new samples testify the successful attempt to reproduce the EB according to the chemical knowledge