Stilbite-Ca is best recognized by its signature sheaf-like or bow-tie crystal clusters that form in vugs within volcanic rock. It is a common zeolite that often appears alongside other minerals like apophyllite and heulandite in basalt cavities, making it a favorite for display specimens.
Is this stilbite-ca?
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 stilbite-ca with a known reference. Stilbite-Ca sits at Mohs 3.5-4 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Stilbite-Ca leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Stilbite-Ca typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: white, colorless, yellow, pink, orange, brown.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: sheaf-like aggregates.
Often confused with
Stilbite-Ca vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside stilbite-ca
Minerals reported to co-occur with stilbite-ca. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- NaCa₄(Si₂₇Al₉)O₇₂·28H₂O
- Mohs hardness
- 3.5-4
- Density
- 2.1-2.2 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Sheaf-like Aggregates
- Cleavage
- Perfect Basal
- Rarity
- Common
- Uses
- Collector, Decorative
- Host rock
- Basaltic Volcanic Cavities
- Typical price
- $10-150 depending on specimen size and clarity
Where rockhounds find stilbite-ca
Classic worldwide localities
- Poona, India
- Teigarhorn, Iceland
- Bay of Fundy, Canada
- New Jersey, USA
- Faroe Islands
Field-hunting tip
Look in basaltic volcanic cavities country — that is the host setting where stilbite-ca typically forms. If you start seeing heulandite, apophyllite, calcite in float, you are in the right ground. Field specimens usually show a sheaf-like aggregates habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify stilbite-ca?+
Where is stilbite-ca found?+
How much is stilbite-ca worth?+
What rocks look like stilbite-ca?+
What minerals are found with stilbite-ca?+
What kind of rock does stilbite-ca form in?+
What is stilbite-ca used for?+
Find stilbite-ca on the map
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