Dumortierite is a fibrous,variably colored aluminum boro silicate mineral. It crystallizes in the orthorhombic system,and whole crystals typically form fibrous aggregates of slender prismatic crystals. These crystals are vitreous and vary in color from brown,blue,and green to more rare violet and pink. In aluminum rich,metamorphosed rocks and pegmatites it occurs disseminated or in thin veins in schists or quartzites,as in this example. It is used in the manufacture of high grade porcelain. It is sometimes mistaken for sodalite and is known to be used as imitation lapis lazuli. Actual height of specimen is 85 mm | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Wiersma, Dirk |
Taille de l’image : | 3744 px × 5116 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |