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The use of natural inorganic pigments in the ceramic industry is steadily increasing. Natural inorganic pigments have low costs, compared with synthetic pigments. Iron oxide is a widely used natural pigment since it presents an ample variety of colours, is non-toxic and has a low cost. The red pigment has been a problem for the ceramic industry because the only one that is considered blood red does not work at temperatures higher than 1100 deg C, Moreover, it is also toxic. Hematite is a natural iron ore, with a stable red colour up to 1000 deg C. However the Fe(3+) ion is very reactive with ceramic glaze compositions, frits and ceramic bodies. In this context, the present work was undertaken with a view to investigating the synthesis processes of hematite particle occlusion in an amorphous silica matrix. Thus, goethite with average particle size between 4 and 2 mm was wet mixed with amorphous silica (surface area of 400 m2/g) in a ball mill for 5h. After homogenization the samples were dried in a laboratory furnace at 110 deg C, deaggregated and subsequently heat-treated in an electric furnace in the 1050-1200 deg C temperature range for 240 min. Finally, the heat-treated samples were analyzed by XRD and the pigment colours were determined by a UV-Vis spectrophotometer. The results indicate that pigment colour is influenced by the particle size of the iron oxide precursor, relative amounts of the oxide precursor and encapsulating matrix, as well as heat-treatment temperature and time (calcination).