mineral

Tumbled smoky quartz (probable)

Quartz, SiO₂; smoky variety colored by irradiation-related defects

AI-generated identification · may be incorrect

Small polished, rounded dark-brown to nearly black translucent specimen with vitreous luster. Quartz has Mohs hardness 7, no cleavage, conchoidal fracture, hexagonal crystal structure, and specific gravity about 2.65; the image cannot confirm these properties.

Identified September 8, 2026More mineral →

Explore Tumbled smoky quartz (probable) 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

Forms in silica-rich hydrothermal veins, pegmatites, and cavities; coloration develops from natural radiation acting on trace aluminum. Quartz spans much of Earth’s geologic history, and this is likely a modern tumbled specimen.

Uses & applications

Used as a low-cost ornamental and collector stone; faceted smoky quartz is used in jewelry, while quartz broadly has major industrial uses in glass, electronics, and abrasives.

Geological facts

The very dark appearance could also represent polished morion quartz, dark agate, or another iron-rich silica material; internal translucency and banding would help distinguish them.

Field identification & locations

Check for glassy luster, translucency at the edges, hardness sufficient to scratch ordinary glass, and absence of bubbles or molded surfaces. Quartz is common worldwide; near 33.5°N, 94°W, gravel-derived quartz and agate are plausible regional sources.