The subject of this book is the analysis of the performance in ceramics of scheelite (CaWO4) and zircon (ZrSiO4). The aesthetics of glazed ceramics and paints depends to a large extent on the so-called opacifiers that give them brightness and pigments that give them color. At present, zircon ZrSiO4 is the main opacifier of industrial ceramic glazes and the base of a widely-used pigment palette (cyan of vanadium in zircon, magenta of hematite in zircon and yellow of praseodymium in zircon). Likewise, scheelite CaWO4 can be used as a good opacifier by addition to glazes and is the basis of...