Dumortierite Quartz
Quartz var. Dumortierite Included Quartz · Semi-Precious Gemstone
Crystal System
Trigonal
Mineral Group
Silicates
Chemical Formula
SiO2 with Al7BO3(SiO4)3O3 inclusions
Formation Process
Hydrothermal and pegmatitic formation where needle-like crystals of dumortierite are engulfed by growing quartz crystals.
About This Crystal
A tumbled stone displaying a deep denim-blue to royal-blue coloration with characteristic fibrous or patchy inclusions of blue dumortierite mineral throughout a translucent to opaque quartz matrix.
Physical Characteristics
Color ranges from dark blue to violet-blue; streak is white; conchoidal fracture; specific gravity around 2.65; vitreous to waxy luster.
Optical Properties
Singly or doubly refractive with a refractive index of approximately 1.544 to 1.553, typically exhibiting no notable pleochroism in the quartz host itself.
Hardness & Durability
Origin Region
Brazil, Madagascar, Namibia, and the USA
Hardness & Durability
Mohs hardness of 7 for the quartz host, making it durable and suitable for everyday jewelry wear.
Care & Maintenance
Clean with warm soapy water and a soft brush; avoid harsh chemicals and prolonged direct sunlight to prevent potential color alteration.
Rarity & Value
Uncommon to rare depending on the density and vividness of the blue inclusions; generally affordable as tumbled stones or cabochons.
Special Characteristics
Contains needle-like or fibrous mineral inclusions of dumortierite trapped inside a host quartz crystal, often creating a mottled or denim-like appearance.
Lore & History
Often associated with the third eye chakra in crystal healing traditions, believed to enhance mental discipline, focus, and patience, though these are traditional beliefs without scientific backing.