RocksdayQuartz vs Rutilated Quartz
How to tell them apart
The second most abundant mineral in Earth's crust. Clear crystals grow as six-sided prisms capped by a pointed termination, and quartz shows up as grains in sand, granite and countless other rocks.
Photo: Didier Descouens, CC BY-SA 4.0
Clear quartz threaded with golden or reddish needles of the mineral rutile.
Photo: James St. John, CC BY 2.0
Key differences
- Plain quartz has no needle inclusions.
Side by side
| Property | Quartz | Rutilated Quartz |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 7 | 7 |
| Luster | Vitreous | Vitreous |
| Streak | White | White |
| Colors | Clear, White, Gray | Clear, Gold |
| Crystal system | Trigonal | Trigonal |
| Specific gravity | 2.65 | 2.65–2.7 |
| Formula | SiO₂ | SiO₂ with TiO₂ needles |
| Found in | Hot Springs, Arkansas; Minas Gerais, Brazil | Minas Gerais and Bahia, Brazil; Madagascar |
Properties that are the same for both are grayed out.
How to identify quartz
- Scratches glass easily and can't be scratched by a steel knife.
- Six-sided prisms with pointed ends when it forms crystals.
- Breaks with curved, shell-like (conchoidal) fractures — no flat cleavage planes.
- Does not fizz in vinegar or dilute acid.
Crystal system: Trigonal
Full Quartz guide →How to identify rutilated quartz
- Clear quartz with fine gold, copper or black needles inside.
- Hardness 7.
- Needles run in straight lines, often criss-crossing.
Crystal system: Trigonal
Full Rutilated Quartz guide →More comparisons
Could you tell them apart from a blurry close-up?
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