A rare blue or violet mineral occurring typically as needles and fibrous masses in gneiss and schist. It consists of an aluminium and iron borosilicate.
More example sentences
- Little known from the east coast, important deposits of dumortierite exist in Rochester and Oreana, Nevada.
- Beautiful blue semi-precious dumortierite nuggets are accented by sparkling 8mm clear Swarovski crystals.
- Detrital dumortierite infrequently has been found in the heavy mineral fraction of sediments.
late 19th century: from the name of V.-E. Dumortier (1802–76), French geologist, + -ite1.
Definition of dumortierite in:
- The US English dictionary