Benauite is a rare strontium-iron phosphate member of the crandallite group typically found as small, thin tabular crystals or as crusts on iron-rich matrices. It is a secondary mineral primarily identified through chemical analysis or XRD due to its superficial resemblance to other phosphate group members. It is highly sought after by mineral collectors specializing in rare phosphates and species from type localities.
Is this benauite?
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 benauite with a known reference. Benauite sits at Mohs 4 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Benauite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Benauite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: white, colorless, yellowish.
- 5Look at form & habitCrystal system: trigonal. Typical habit: tabular crystals, drusy crusts.
Often confused with
Benauite vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside benauite
Minerals reported to co-occur with benauite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- SrFe₃(PO₄)₂(OH)₅·H₂O
- Mohs hardness
- 4
- Density
- 3.84 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Trigonal
- Crystal habit
- Tabular Crystals, Drusy Crusts
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Hydrothermal Veins in Iron Ore Deposits
- Typical price
- $50-300 per specimen
Where rockhounds find benauite
Classic worldwide localities
- Benau, Germany
- Långban, Sweden
Field-hunting tip
Look in hydrothermal veins in iron ore deposits country — that is the host setting where benauite typically forms. If you start seeing hematite, quartz, goethite in float, you are in the right ground. Field specimens usually show a tabular crystals, drusy crusts habit, so train your eye for that shape before scanning the outcrop.





