Vantasselite is a rare hydrous aluminum phosphate mineral known primarily from its type locality near Vantage, Washington. It typically occurs as delicate, pearly-white, radiating rosettes or micaceous clusters formed within amygdaloidal cavities in basalt. Collectors prize these fragile formations due to their distinct crystal habit and restricted geographic distribution.
Is this vantasselite?
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 vantasselite with a known reference. Vantasselite sits at Mohs 2-2.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: pearly on cleavages.
- 4Match the color rangeCompare against the expected color range: pearl white.
- 5Look at form & habitCrystal system: orthorhombic. Typical habit: rosette.
Often confused with
Vantasselite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Wavellite is the harder of the two (Mohs 3.5-4 vs. 2-2.5); luster reads pearly on cleavages on Vantasselite and vitreous to resinous, pearly on Wavellite.
How to tell apart: Variscite is the harder of the two (Mohs 4.5 vs. 2-2.5); luster reads pearly on cleavages on Vantasselite and vitreous to waxy on Variscite.
Often found alongside vantasselite
Minerals reported to co-occur with vantasselite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Al₄(PO₄)₃(OH)₃·9H₂O
- Mohs hardness
- 2-2.5
- Density
- 2.30 g/cm³
- Colors
- Streak
- White
- Luster
- Pearly on cleavages
- Transparency
- Transparent to translucent
- Crystal system
- Orthorhombic
- Crystal habit
- Rosette
- Cleavage
- On {001}, micaceous; imperfect on {010}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- On dumps in a quartzite quarry, in quartz veinlets or lining schistosity planes
Where rockhounds find vantasselite
Classic worldwide localities
- Found about one km north of Bihain, Belgium
Field-hunting tip
Where it forms: On dumps in a quartzite quarry, in quartz veinlets or lining schistosity planes. If you start seeing wavellite, cacoxenite, variscite in float, you are in the right ground. Typical habit: rosette. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify vantasselite?+
Where is vantasselite found?+
What rocks look like vantasselite?+
What minerals are found with vantasselite?+
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What is vantasselite used for?+
Find vantasselite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
