Rutile pigments (where , 0.05, 0.10, 0.20, 0.30 and 0.50) prepared by solid-state reaction are investigated. Chromium is chromophore (coloring ion) and niobium is counterion (charge-compensating element for electroneutrality). The effect of composition (x), calcination temperature (850, 900, 950, 1000, 1050, 1100 and 1150°C), and starting titanium compounds (anatase TiO2, hydrated anatase paste, TiOSO4 2H2O, and hydrated Na2Ti4O9 paste) on their color properties into organic matrix and particle size distribution was observed. According to the highest chroma C and visual color evaluation, yellow and orange pigments were selected as in color the most interesting. They have concentration or 0.10 and are prepared from anatase TiO2 and TiOSO4 2H2O at temperature 1050°C. 1. Introduction The goal of this work was to evaluate the influence of composition ( , 0.05, 0.10, 0.20, 0.30, and 0.50), calcination temperature (850, 900, 950, 1000, 1050, 1100, and 1150°C), and starting titanium compounds (anatase TiO2, hydrated anatase paste, TiOSO4·2H2O, and hydrated Na2Ti4O9 paste) on color properties and particle size distribution of the rutile pigments into organic matrix. Sb is the most widely used charge-compensating element for commercial rutile pigments, but it is ecologically problematic. This is the reason why we studied rutile pigments with Nb, which can also offer interesting pigments. Raw materials have an effect on properties of pigments as well; therefore, four various starting titanium compounds were used. In addition, selected pigments were analyzed by X-ray powder diffraction. Rutile pigments are commercially manufactured pigments based on tetragonal mineral rutile (TiO2) and they belong to the most important group of complex inorganic color pigments (CICPs) [1]. They are used for coloring ceramic glazes and porcelain enamels, plastics, inks, building materials, external paints, foods, and so forth [2, 3]. Solid solutions of chromium- (III) doped rutile have gained considerable recognition as durable, chemical resistant inorganic pigments with thermal stability over 1000°C [4]. The crystal structure of rutile pigments is modified by doping elements (chromophores and counterions), which vary the cell parameters [5]. In 1962, Hund issued a patent on the preparation of rutile pigments, which demonstrates the ability of rutile to form solid solutions with many compounds. Three fundamental rules were given for the formation of a rutile pigment. Firstly, substitutional atoms must have ionic sizes similar to Ti4+ (0.61？？) or O2？ (1.40？？). Secondly, charge
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