Bentorite is a very rare member of the ettringite group typically found as small, delicate, pinkish-violet prismatic crystals. It is primarily known from its type locality in the Hatrurim Basin of Israel, occurring in high-temperature metamorphic environments. Due to its softness and high water content, specimens should be handled with care and stored in a low-humidity environment.
Is this bentorite?
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 bentorite with a known reference. Bentorite sits at Mohs 3 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Bentorite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Bentorite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: pink, violet, white.
- 5Look at form & habitCrystal system: hexagonal. Typical habit: prismatic crystals.
Often confused with
Bentorite vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside bentorite
Minerals reported to co-occur with bentorite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Ca₆(Cr,Al)₂(SO₄)₃(OH)₁₂·26H₂O
- Mohs hardness
- 3
- Density
- 1.79 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Hexagonal
- Crystal habit
- Prismatic Crystals
- Cleavage
- Perfect
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Metamorphic Rocks of The Hatrurim Formation
- Typical price
- $50-500 depending on crystal size and quality
Where rockhounds find bentorite
1 mapped spotsClassic worldwide localities
- Hatrurim Basin, Israel
Field-hunting tip
Look in metamorphic rocks of the hatrurim formation country — that is the host setting where bentorite typically forms. If you start seeing calcite, portlandite, hydrocalumite in float, you are in the right ground. Field specimens usually show a prismatic crystals habit, so train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in Utah — start trip planning there.
Common questions
How do you identify bentorite?+
Where is bentorite found?+
Can I find bentorite in the United States?+
How much is bentorite worth?+
What rocks look like bentorite?+
What minerals are found with bentorite?+
What kind of rock does bentorite form in?+
What is bentorite used for?+
Find bentorite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
