mineral
Polished smoky quartz point
Quartz, silicon dioxide (SiO₂), likely smoky variety
AI-generated identification · may be incorrectMohs hardness 7; translucent to opaque brown-gray color with vitreous luster and typically hexagonal crystal structure. The elongated polished form obscures natural cleavage; quartz has poor cleavage and conchoidal fracture, with specific gravity about 2.65.
Identified More mineral →
Explore Polished smoky quartz point in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Mohs hardness 7; translucent to opaque brown-gray color with vitreous luster and typically hexagonal crystal structure. The elongated polished form obscures natural cleavage; quartz has poor cleavage and conchoidal fracture, with specific gravity about 2.65.
Formation & geological history
Smoky coloration results from radiation-induced defects, commonly in granitic pegmatites, hydrothermal veins, and cavities. Quartz formed across many geological ages, so age cannot be determined from the specimen alone.
Uses & applications
Used as a decorative crystal, lapidary object, and occasional gemstone; quartz is also important industrially in glass, ceramics, electronics, and abrasives. This polished specimen is mainly collectible or ornamental.
Geological facts
The dark color may also reflect inclusions or surface coating, and visual inspection cannot confirm whether it is natural smoky quartz. Quartz is one of Earth’s most abundant minerals.
Field identification & locations
Look for glassy luster, hardness sufficient to scratch ordinary glass, and absence of bubbles; smoky quartz commonly shows uneven natural zoning. Common sources include Brazil, Madagascar, Switzerland, and the United States.
