Dumortierite is a fibrous variably colored mineral of Aluminium boro silicate or Al7BO3(SiO4)3O3. Dumortierite crystals are vitreous. They may vary in color from brown, blue and green to rarer colors like pink and violet. Variation in color happens when aluminium is substituted by the other trivalent elements.

Its hardness is 7 on Moh’ s scale. Crystals exhibit pleochroism from red to blue and blue to violet. Pleochroism is an optical phenomenon in which a substance appears to be of different colors when observed at different angles, especially with a polarized light.

Dumortierite quartz is a blue colored quartz containing abundant dumortierite inclusions. Dumortierite was first described in 1881 for an occurrence in the Rhône-Alps of France. It was and named after the French paleontologist Eugene Dumortier (1803-1873).

Dumortierite is used in the manufacture of high grade porcelain. It is sometimes used as imitation lapis lazuli. All the naturally occurring blue quartz are translucent or opaque.

Dumortierite deposits are found in Madagascar, Mozambique, Namibia, Sri Lanka, India, France, Italy, Poland and Norway, Austria, Brazil, Canada and Russia.