mineral

Smoky quartz crystal

Quartz, silicon dioxide (SiO₂), likely smoky variety

AI-generated identification · may be incorrect

Hardness 7 Mohs; transparent to translucent gray-brown color with vitreous luster and a hexagonal crystal structure. The specimen appears naturally terminated but may be polished or shaped; quartz has no cleavage and conchoidal fracture.

Identified August 28, 2026More mineral →

Explore Smoky quartz crystal in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

Physical properties

Formation & geological history

Smoky quartz forms in cavities of granitic and pegmatitic rocks when trace aluminum and natural radiation darken quartz during growth, commonly in Precambrian to younger continental crust. Exact locality and age cannot be determined from the image.

Uses & applications

Used as a collectible mineral and occasional gemstone; quartz is also important in glass, electronics, abrasives, and engineered stone. This small included crystal has modest commercial value.

Geological facts

The dark internal features may be mineral inclusions, fractures, or coatings, so visual identification as smoky quartz is provisional. Quartz is one of Earth’s most abundant and chemically durable minerals.

Field identification & locations

Identify by its glassy luster, lack of cleavage, six-sided prismatic form, pointed termination, and ability to scratch glass. Common sources include Brazil, Madagascar, Switzerland, the United States, and worldwide granitic terrains.