SYNTHESIS OF A PINK ZIRCON PIGMENT

A pink zircon pigment of the inclusion type, (ZrSiO//4)//1// minus //x. XFe//2O//3, has been synthesized by a thermal process from the starting oxides ZrO//2 and SiO//2. Green vitriol (ferrous sulphate) or ferric oxide-hydroxide has been used as the chromophore (source of the inclusions). The reactions in the synthesis have been followed by thermal analysis, by analysis of the products prepared under isothermal conditions at various temperatures and during various reaction times in an electric furnace, and by tableting (marking) experiments. Two types of commercial ZrO//2 have been used, both of them being raw materials for the industrial production of zircon pigments. The reactivity of these oxides has been evaluated, the conditions of the pigments synthesis have been determined and the reaction mechanism and kinetics have been investigated.