Heulandite-Ba is a rare barium-dominant member of the zeolite group that typically forms characteristic coffin-shaped tabular crystals. It is most commonly found in cavities within basaltic rocks where it crystallized from hydrothermal fluids. Collectors often distinguish it from other heulandite species through chemical analysis due to its visual similarity to calcium-dominant varieties.
Is this heulandite-ba?
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 heulandite-ba with a known reference. Heulandite-Ba 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. Heulandite-Ba leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Heulandite-Ba typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: white, colorless, yellow, orange, brown, pink.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: tabular crystals with coffin-like habit.
Often confused with
Heulandite-Ba vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside heulandite-ba
Minerals reported to co-occur with heulandite-ba. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (Ba,Sr,Ca,Na,K)₅(Si₂₇Al₉)O₇₂·26H₂O
- Mohs hardness
- 3.5-4
- Density
- 2.18-2.22 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Tabular Crystals with Coffin-like Habit
- Cleavage
- Perfect On {010}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Basaltic Vugs and Cavities
- Typical price
- $20-150 thumbnail to cabinet specimen
Where rockhounds find heulandite-ba
Classic worldwide localities
- Kurumini, Japan
- Aranga, New Zealand
- Maharashtra, India
- Scotland
Field-hunting tip
Look in basaltic vugs and cavities country — that is the host setting where heulandite-ba typically forms. If you start seeing quartz, calcite, apophyllite in float, you are in the right ground. Field specimens usually show a tabular crystals with coffin-like habit habit, so train your eye for that shape before scanning the outcrop.





