Crystal guide
How to Identify Clear Quartz
SiO₂
Clear quartz (rock crystal) is transparent hexagonal SiO₂ — the Mohs 7 collector point. Identify it by prism striations, vitreous terminations, and hardness that scratches glass (unlike selenite or soft glass lookalikes).
About Clear Quartz
Clear quartz (rock crystal) is transparent hexagonal SiO₂ — the Mohs 7 collector point. Identify it by prism striations, vitreous terminations, and hardness that scratches glass (unlike selenite or soft glass lookalikes).
Clear Quartz is filed under crystals in the RockScan directory. Composition: Silicon dioxide. It forms via hydrothermal veins, pegmatites, geodes. Typical occurrence: Worldwide. For the broader method, see how to identify rock types.
Clear Quartz properties
| Mohs hardness | 7 |
|---|---|
| Class | crystal |
| Scientific name | SiO₂ |
| Color | Colorless |
| Luster | Vitreous |
| Crystal system / texture | Trigonal |
| Composition | Silicon dioxide |
| Formation | Hydrothermal veins, pegmatites, geodes |
| Occurrence | Worldwide |
How to identify Clear Quartz
- Clear hexagonal prisms; Mohs 7.
- Vitreous; conchoidal fracture.
- Horizontal striations on prism faces common.
Lookalikes to rule out
- Glass: Glass bubbles; quartz has crystal striations and Mohs 7.
- Selenite: Selenite is Mohs 2; clear quartz is Mohs 7.
- Topaz: Topaz cleavage vs quartz fracture.
Photo tips for Clear Quartz ID
- Show prism striations and terminations.
- Minimize glare on clear faces.
- Include phantom or inclusion details if present.
Snap one specimen in natural light, then open the result in the online studio or the rock identifier app.
Clear Quartz FAQ
How do you identify clear quartz?
Transparent quartz points with Mohs 7 and hexagonal habit. Soft clear minerals fail the hardness check.
Clear quartz vs glass?
Crystal faces/striations and hardness; glass may show bubbles.
Is rock crystal quartz?
Yes — rock crystal means clear quartz.
How to identify clear quartz
Collectors search “how to identify clear quartz” (rock crystal) when a transparent point might be glass, selenite, or topaz. Use this field checklist:
- Habit: hexagonal prisms with terminations; horizontal striations on prism faces are classic.
- Hardness: Mohs 7 — scratches glass; selenite (~2) fails immediately.
- Clarity cues: vitreous, conchoidal fracture; glass often shows bubbles; quartz usually does not.
- Not cleavage slabs: topaz has cleavage; quartz breaks with curved fracture, not perfect cleavage sheets.
- Photo first: show striations + tip, minimize glare, then confirm with RockScan.
Clear quartz vs glass vs selenite vs topaz
- Glass: Bubbles and molded edges common; quartz shows crystal striations and Mohs 7.
- Selenite: Mohs 2 gypsum; clear quartz is Mohs 7 and will not scratch with a fingernail.
- Topaz: Perfect cleavage vs quartz fracture; different crystal chemistry and optics.
Photo tips for clear quartz ID
Prism striations, terminations, and soft light to avoid glare; include phantoms/inclusions if present. Compare quartz, amethyst, and gypsum, then confirm in the online studio or rock identifier app.
Related crystals to compare
Browse all: rocks · minerals · crystals · directory · what rock is this · rock vs mineral vs crystal. Confirm with the online studio or rock identifier app.