$Smoky quartz (possibly smoky quartz/chalcedony) (Quartz, silicon dioxide (SiO₂), likely natural smoky quartz with conchoidal fracture) — mineral$

mineral

Smoky quartz (possibly smoky quartz/chalcedony)

Quartz, silicon dioxide (SiO₂), likely natural smoky quartz with conchoidal fracture

AI-generated identification · may be incorrect

Hardness 7 Mohs; translucent gray-brown to smoky purple, vitreous luster, and no obvious cleavage. Quartz is trigonal and has a specific gravity near 2.65; the rough edges and conchoidal fractures are consistent with quartz.

Identified September 13, 2026More mineral →

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At a glance

Common name: Smoky quartz (possibly smoky quartz/chalcedony)
Scientific name: Quartz, silicon dioxide (SiO₂), likely natural smoky quartz with conchoidal fracture
Category: mineral
Identified: September 13, 2026
Method: Standard

AI Estimated Value

Approximately $3–$20 for a small rough/common piece; $25–$150+ if it proves to be an attractive, well-formed smoky-quartz specimen.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Smoky color generally forms when natural radiation activates aluminum impurities in quartz, commonly in granitic pegmatites, hydrothermal veins, and alpine cavities. Crystals may range from ancient geological settings to relatively young vein deposits.

Uses & applications

Used as a collectible mineral and occasionally in cabochons or jewelry; quartz is also important industrially in glass, electronics, abrasives, and engineered stone.

Geological facts

The specimen may alternatively be dark chalcedony or agate, which is also microcrystalline quartz; a polished surface or testing is needed for certainty. Genuine smoky quartz can fade with strong heating or sunlight.

Field identification & locations

Look for glassy luster, conchoidal fracture, translucency, and scratch resistance greater than ordinary steel; it should scratch glass but not be scratched by a steel knife. Common sources include Brazil, Madagascar, Switzerland, the United States, and Scotland.