mineral
Dumortierite Quartz
Aluminum Borate Silicate Oxide (Al7BO3(SiO4)3O3)
Hardness: 7 to 8.5 (Mohs), Color: Characteristic blue, violet-blue, or indigo, Luster: Vitreous to dull, Crystal structure: Orthorhombic, Cleavage: Good on {100}
- Hardness
- 7 to 8
Identified More mineral →
Explore Dumortierite Quartz in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 7 to 8.5 (Mohs), Color: Characteristic blue, violet-blue, or indigo, Luster: Vitreous to dull, Crystal structure: Orthorhombic, Cleavage: Good on {100}
Formation & geological history
Typically forms in regional metamorphic rocks rich in aluminum, such as gneiss or schist, and sometimes in boron-rich pegmatites and hydrothermally altered rocks.
Uses & applications
Used as a decorative stone, in jewelry (beads, cabochons), and in the production of high-grade porcelain and ceramics due to its high aluminum content.
Geological facts
It is often named 'Blue Quartz' when it occurs as inclusions in quartz. It was named after the French paleontologist Eugène Dumortier who first observed it in the late 19th century.
Field identification & locations
Identified by its distinct waxy to vitreous luster and deep blue color that does not streak. Common sources include Brazil, Madagascar, and Sri Lanka. Collectors look for pieces with high clarity or interesting fibrous inclusions.
More like this
Other mineral specimens
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Sandstone with Mineral Veining or Crust
Sedimentary Sandstone (mostly SiO2 with Fe2O3 tinting)
sedimentary
Schist
Schist
Metamorphic
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Gypsum (variety Selenite or Alabaster)
Calcium sulfate dihydrate (CaSO4·2H2O)
Mineral
Nephrite Jade
Nephrite
Mineral/Rock