Chromatic study on the coloration mechanism of iron zircon pigment

To clearly understand the coloration mechanism of iron zircon pigment based on encapsulating or doping, FeF 3 , as a mineralizer and a Fe source, is introduced into this pigment prepared by sol-gel method. The results show that Fe 3+ cation is doped into zircon by means of replacing zirconium ion , which results in the formation of Fe x -ZrSiO 4 solid solution when the Fe 3+ content is less than 2.25mol%. However, iron oxide (α-Fe 2 O 3 ) will be generated and be encapsulated in zircon when the Fe 3+ content is over 2.25mol%. The a ∗ value of Fe x -ZrSiO 4 solid solution is 20.01, which is similar to that of the commercial pigment prepared by solid reaction. The color of iron zircon pigment is mainly determined by the encapsulated layer of Fe x -ZrSiO 4 solid solution, rather than the core of α-Fe 2 O 3 .