Various titanium suboxide powders have been produced by solid-state reaction between TiO2 powders or TiO2 coated mica and silicon as reducing agent at temperatures below 1000 degrees C in an inert atmosphere. The process leads to blue-grey powders with colour characteristics depending on the composition and the structure of the materials. Titanium suboxides like Ti2O3, gamma-Ti3O5, Ti4O7, Ti7O13, Ti8O15 Or Ti9O17 are formed during the reduction processes. Calcium chloride as an additive, type of atmosphere as well as temperature have an important influence on the composition and on the colour of the powders. The titanium suboxide powders were characterized by XRD.