mineral

Blue Quartz

Silicon dioxide (SiO2) with inclusions

Hardness 7 on Mohs scale. Color: Blue-grey to indigo. Luster: Vitreous to waxy. Crystal system: Trigonal. Specific gravity: 2.65.

Color: Blue-grey to indigo
Luster: Vitreous to waxy

Identified July 15, 2026More mineral →

Explore Blue Quartz in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness 7 on Mohs scale. Color: Blue-grey to indigo. Luster: Vitreous to waxy. Crystal system: Trigonal. Specific gravity: 2.65.

Formation & geological history

Formed in igneous or metamorphic environments where inclusions such as crocidolite, tourmaline, or rutile create a blue hue through the Rayleigh scattering of light.

Uses & applications

Used primarily in decorative applications, jewelry making, lapidary arts, and as a collector's specimen. Sometimes used in ornamental landscaping.

Geological facts

Unlike many blue gemstones, the color in blue quartz is usually caused by the scattering of light from microscopic inclusions rather than chemical substitution in the quartz lattice.

Field identification & locations

Identify by its hardness (scratches glass), lack of cleavage, and the characteristic 'denim' blue color that often appears slightly hazy or opaque. Commonly found in Brazil and Virginia (USA).