Berlinite is a rare phosphate mineral that is structurally isomorphous with quartz, often leading to confusion between the two. It typically occurs as white or colorless massive aggregates, though rare distinct crystals can be found in specialized hydrothermal environments or phosphate-rich pegmatites.
Is this berlinite?
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 berlinite with a known reference. Berlinite sits at Mohs ~6.5, 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: vitreous.
- 4Match the color rangeCompare against the expected color range: colorless, gray, gray pink, light pink.
- 5Look at form & habitCrystal system: trigonal. Typical habit: massive, granular, or rare hexagonal prisms.
Often confused with
Berlinite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside berlinite
Minerals reported to co-occur with berlinite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- AlPO₄
- Mohs hardness
- ~6.5
- Density
- 2.64-2.66 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent to translucent
- Crystal system
- Trigonal
- Crystal habit
- Massive, granular, or rare hexagonal prisms
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector, Scientific research
- Host rock
- A rare high-temperature hydrothermal or metasomatic mineral; also in a cave in heavily compacted phosphate-bearing clay sediments that underwent heating, probably by in situ combustion of guano
Where rockhounds find berlinite
Classic worldwide localities
- Västanå mine, near Näsum, Skåne, and at Hålsjöberg, Värmland, Sweden
- Rwanda, in the Buranga and Rusororo pegmatites, Gatumba district
- Mt. Perry, 75 km southwest of Bundaberg, Queensland, and at Paddy’s River mine, Australian Capital Territory, Australia
- Sapucaia pegmatite mine, about 50 km east-southeast of Governador Valadares, Minas Gerais, Brazil
- Cioclovina Cave, Sureanu Mountains, Romania
Field-hunting tip
Where it forms: A rare high-temperature hydrothermal or metasomatic mineral; also in a cave in heavily compacted phosphate-bearing clay sediments that underwent heating, probably by in situ combustion of guano. If you start seeing augelite, attakolite, kyanite in float, you are in the right ground. Typical habit: massive, granular, or rare hexagonal prisms. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify berlinite?+
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What rocks look like berlinite?+
What minerals are found with berlinite?+
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Find berlinite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
