Smoky quartz
At a glance
- Type
- Mineral
- Group
- Oxide
- Crystal system
- Trigonal
- Hardness
- Hard (5.5 to 7.5)
- Density
- Medium (2.5 to 3.2)
- Occurs in
- Igneous rocks
- Foliation
- Not layered
- Colour
- Grey, Black, Brown
- Lustre
- Glassy
- Use
- Gemstone, Jewellery
- Difficulty in WildGuessr
- Medium
Did you know?
- Smoky quartz gets its brown-grey colour from natural radiation acting on traces of aluminium in the crystal.
- Smoky quartz from the Cairngorm Mountains is called cairngorm and is a traditional Scottish gem.
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Classification, names and conservation status come from Wikidata (CC0), the photo from Wikimedia Commons. Wikidata Q429935 · All stones · All entries