Phosphoellenbergerite is an extremely rare phosphate mineral first discovered in ultrahigh-pressure metamorphic rocks. It typically appears as small, prismatic crystals that are colorless or pale pink and are structurally closely related to ellenbergerite.
Is this phosphoellenbergerite?
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 phosphoellenbergerite with a known reference. Phosphoellenbergerite sits at Mohs 4-4.5, 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 to subresinous.
- 4Match the color rangeCompare against the expected color range: blue.
- 5Look at form & habitCrystal system: orthorhombic. Typical habit: anhedral grains.
Often confused with
Phosphoellenbergerite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside phosphoellenbergerite
Minerals reported to co-occur with phosphoellenbergerite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (Mg,□)₂Mg₁₂(PO₄,PO₃OH)₆(PO₃OH,CO₃)₂(OH)₆
- Mohs hardness
- 4-4.5
- Density
- 3.10-3.29 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous to subresinous
- Transparency
- Transparent to translucent
- Crystal system
- Orthorhombic
- Crystal habit
- Anhedral grains
- Cleavage
- On {010}, poor
- Rarity
- Rare
- Uses
- Collector
- Host rock
- An alteration product of triphylite in zoned complex granite pegmatites
Where rockhounds find phosphoellenbergerite
Classic worldwide localities
- Palermo #1 mine, near North Groton, Grafton Co., New Hampshire, USA
- Dan Patch mine, 1.5 km west of Keystone, Pennington Co., and the Bull Moose and Tip Top mines, near Custer, Custer Co., South Dakota, USA
- Hagendorf, Bavaria, Germany
- Mangualde pegmatite, near Mesquitela, Portugal
- Énio pegmatite mine, northeast of Galiléia, Minas Gerais, Brazil
- El Criollo pegmatite, Cerro Blanco, Tanti district, 45 km west of Córdoba, Córdoba Province, Argentina
Field-hunting tip
Where it forms: An alteration product of triphylite in zoned complex granite pegmatites. If you start seeing ludlamite, vivianite, huréaulite in float, you are in the right ground. Typical habit: anhedral grains. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify phosphoellenbergerite?+
Where is phosphoellenbergerite found?+
What rocks look like phosphoellenbergerite?+
What minerals are found with phosphoellenbergerite?+
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What is phosphoellenbergerite used for?+
Find phosphoellenbergerite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
