Smoky Quartz
Smoky quartz is a brown to black variety of quartz colored by natural irradiation. The national gem of Scotland, it ranges from light tan to nearly opaque black.
Smoky Quartz properties at a glance
| Type | Quartz Family |
|---|---|
| Chemical formula | SiO2 |
| Mohs hardness | 7 |
| Crystal system | hexagonal |
| Luster | vitreous |
| Streak | White |
| Cleavage | None |
| Fracture | Conchoidal |
| Specific gravity | 2.65 |
| Transparency | transparent |
| Common colors | Brown, Gray, Black |
| Rarity | common |
Geology & background
Forms when clear quartz is exposed to natural radiation from nearby rocks, causing color centers.
Scottish Highlanders traditionally set smoky quartz in brooches and kilt pins.
How to identify Smoky Quartz
- Check whether the specimen's color and texture match typical Smoky Quartz examples.
- Photograph a fresh surface in natural light and avoid shadows, glare, or wet surfaces.
- Use hardness, streak, luster, grain size, and locality together; no single trait is enough for every specimen.
Where Smoky Quartz is found
Smoky Quartz is reported from multiple localities or geological settings. Exact locality should be verified from specimen provenance, maps, or field notes.
How much is Smoky Quartz worth?
| Entry-level specimen | $5 |
|---|---|
| Typical collector specimen | $30 |
| Premium specimen | $150+ |
Value depends on size, condition, color, crystal quality, locality, rarity, preparation, and provenance. Treat this as educational guidance, not an appraisal.
Common uses
- Jewelry
- Decorative objects
- Spiritual practices
Interesting facts
- National gem of Scotland
- Very dark smoky quartz is called 'morion'
- Color can be artificially induced through irradiation
Care & safety
Treat Smoky Quartz as a collector specimen unless hardness, cleavage, and fracture are confirmed.
Avoid inhaling dust. Do not cut, grind, or polish unknown specimens without eye protection and a properly rated respirator.
.jpg?width=320)