mineral

Blue Quartz (Dumortierite Quartz)

SiO2 with inclusions of AlAl6BSi3O18

Hardness: 7 Mohs; Color: Blue, indigo, or violet-blue; Luster: Vitreous to waxy; Crystal structure: Hexagonal/Trigonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65-3.3

Hardness: 7 Mohs
Color: Blue, indigo, or violet-blue
Luster: Vitreous to waxy

Identified May 29, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; Color: Blue, indigo, or violet-blue; Luster: Vitreous to waxy; Crystal structure: Hexagonal/Trigonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65-3.3

Formation & geological history

Typically formed through metamorphic processes where quartz remains crystallized while acicular inclusions of dumortierite become trapped within the lattice, often in pegmatites or metamorphic rocks during the Paleozoic or Precambrian eras.

Uses & applications

Used primarily in lapidary arts for cabochons, beads, and decorative carvings. It is also a popular collector's mineral and used in metaphysical practices for its purported calming effects.

Geological facts

Unlike sapphire, blue quartz gets its color from microscopic inclusions rather than trace elements in the silicon-oxygen structure. It is one of the rarer color variations of natural quartz.

Field identification & locations

Identified by its distinctive blue color that does not wipe off (internal) and its high hardness which can scratch glass. Commonly found in Brazil, India, and Norway. Collectors should look for a uniform blue saturation.

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