mineral

Blue quartz (likely dumortierite-in-quartz)

Quartz, SiO₂, with blue dumortierite inclusions

AI-generated identification · may be incorrect

Typically pale to medium blue with darker blue patches, vitreous luster, and granular or massive texture; quartz hardness is 7 Mohs, with no cleavage and conchoidal fracture. The specimen appears naturally rounded or tumbled.

Identified August 28, 2026More mineral →

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Physical properties

Formation & geological history

Forms when dumortierite crystallizes as inclusions within quartz during hydrothermal or metamorphic processes; the visible specimen cannot establish a precise age. Common sources include Brazil, Madagascar, and parts of the United States.

Uses & applications

Used as a lapidary and ornamental material for cabochons, beads, carvings, and small polished specimens; modest collector interest.

Geological facts

Blue quartz is colored by microscopic mineral inclusions rather than the quartz itself. It is often confused with blue aventurine, which generally contains reflective mica or fuchsite.

Field identification & locations

Identify by its glassy luster, hardness, lack of cleavage, and blue internal inclusions; it should scratch ordinary glass but not be scratched by a steel knife. Exact identification would require magnification or testing because dyed quartz and blue chalcedony can look similar.