A quartz cluster is a group of terminated crystals growing together from a common matrix, often in a striking geometric arrangement. Collectors prize sharp, clean terminations and either high clarity or attractive inclusions. Clusters form in hydrothermal vein systems where open space lets the crystals grow undisturbed.
Is this quartz cluster?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch quartz cluster with a known reference. Quartz Cluster sits at Mohs 7, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Quartz Cluster leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Quartz Cluster typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: colorless, white, milky.
- 5Look at form & habitCrystal system: trigonal. Typical habit: prismatic clusters.
Often confused with
Quartz Cluster vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Quartz Cluster is noticeably harder (Mohs 7 vs. 3).
How to tell apart: Quartz Cluster is noticeably harder (Mohs 7 vs. 4.5-5); luster reads vitreous on Quartz Cluster and vitreous to pearly on Apophyllite.
Often found alongside quartz cluster
Minerals reported to co-occur with quartz cluster. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- SiO₂
- Mohs hardness
- 7
- Density
- 2.65 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Trigonal
- Crystal habit
- Prismatic Clusters
- Cleavage
- None
- Rarity
- Common
- Uses
- Collector, Decorative, Lapidary
- Host rock
- Hydrothermal Veins and Alpine Clefts
Where rockhounds find quartz cluster
2 mapped spotsClassic worldwide localities
- Arkansas, USA
- Diamantina, Brazil
- Himalayas, Pakistan
- Madagascar
- Switzerland
Field-hunting tip
Look in hydrothermal veins and alpine clefts country, the host setting where quartz cluster typically forms. If you start seeing adularia, chlorite, hematite in float, you are in the right ground. Field specimens usually show a prismatic clusters habit, so train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in New Mexico. Start trip planning there.
More quartz cluster photos
Common questions
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Find quartz cluster on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
