Cactus Quartz, often referred to as Spirit Quartz, is characterized by a central prismatic crystal covered in a multitude of smaller, druzy crystals. These pieces are highly sought after by collectors for their unique, spiky appearance and often vibrant purple or yellow coloration caused by inclusions.
Is this cactus quartz?
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 cactus quartz with a known reference. Cactus Quartz 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. Cactus Quartz leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Cactus Quartz typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: purple, white, yellow, gray, citrine.
- 5Look at form & habitCrystal system: trigonal. Typical habit: drusy-covered prismatic crystals.
Often confused with
Cactus Quartz vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside cactus quartz
Minerals reported to co-occur with cactus quartz. 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
- Translucent
- Crystal system
- Trigonal
- Crystal habit
- Drusy-covered Prismatic Crystals
- Cleavage
- None
- Rarity
- Uncommon
- Uses
- Collector, Decorative
- Host rock
- Hydrothermal Veins in Rhyolite or Quartzite
- Typical price
- $10-150 depending on size and crystal definition
Where rockhounds find cactus quartz
Classic worldwide localities
- Magaliesberg Mountains, South Africa
- Boekenhouthoek, South Africa
Field-hunting tip
Look in hydrothermal veins in rhyolite or quartzite country — that is the host setting where cactus quartz typically forms. If you start seeing hematite, goethite, lepidocrocite in float, you are in the right ground. Field specimens usually show a drusy-covered prismatic crystals habit, so train your eye for that shape before scanning the outcrop.




