Iangreyite is a very rare aluminum phosphate mineral typically found as small, thin, pearly white plates or crusts. It is most commonly identified in phosphate-rich mineral assemblages, requiring professional chemical analysis for positive identification due to its similarity to other rare phosphates.
Is this iangreyite?
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 iangreyite with a known reference. Iangreyite 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. Iangreyite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Iangreyite typically shows a pearly luster.
- 4Match the color rangeCompare against the expected color range: white, pale yellow.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: platy crystals, crusts, aggregates.
Often confused with
Iangreyite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside iangreyite
Minerals reported to co-occur with iangreyite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Al₇(PO₄)₄(OH)₉·2H₂O
- Mohs hardness
- 3
- Density
- 2.95 g/cm³
- Colors
- Streak
- White
- Luster
- Pearly
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Platy Crystals, Crusts, Aggregates
- Cleavage
- Perfect
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Phosphate-rich Pegmatites and Hydrothermal Veins
- Typical price
- $50-300 per specimen
Where rockhounds find iangreyite
Classic worldwide localities
- Ninghanboun Hills, Western Australia
- Santa Rita mine, Minas Gerais, Brazil
Field-hunting tip
Look in phosphate-rich pegmatites and hydrothermal veins country, the host setting where iangreyite typically forms. If you start seeing wavellite, variscite, crandallite in float, you are in the right ground. Field specimens usually show a platy crystals, crusts, aggregates habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify iangreyite?+
Where is iangreyite found?+
How much is iangreyite worth?+
What rocks look like iangreyite?+
What minerals are found with iangreyite?+
What kind of rock does iangreyite form in?+
What is iangreyite used for?+
Find iangreyite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
