Quartz Family · common
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.
Also known as: brown quartz, scottish gem, morion.
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.
Full Smoky Quartz identification guide: checklist, home tests and look-alikes →
Smoky Quartz vs similar stones
Not sure it isn't something else? Side-by-side comparisons with the stones most often confused with Smoky Quartz.
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.
Smoky Quartz FAQ
What is 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.
How much is Smoky Quartz worth?
Entry-level Smoky Quartz specimens sell for around $5, a typical collector specimen for about $30, and premium pieces for $150 or more. Value depends on size, condition, color, crystal quality, locality, rarity, preparation, and provenance. Treat this as educational guidance, not an appraisal.
How hard is Smoky Quartz?
Smoky Quartz has a Mohs hardness of 7. It scratches glass and a steel knife and cannot be scratched by a steel file.
Where is Smoky Quartz found?
Notable sources of Smoky Quartz include Brazil, Switzerland, Colorado, USA, and Australia. Forms when clear quartz is exposed to natural radiation from nearby rocks, causing color centers..
What is Smoky Quartz used for?
Smoky Quartz is used for jewelry, decorative objects, and spiritual practices.
