Nahpoite is an extremely rare phosphate mineral typically found as small, thin, platy crystals or white granular masses within phosphate-rich concretions. It was first identified in the Rapid Creek area of the Yukon, where it occurs as a late-stage mineral in association with various iron and aluminum phosphates.
Is this nahpoite?
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 nahpoite with a known reference. Nahpoite sits at Mohs 1-3, 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: dull.
- 4Match the color rangeCompare against the expected color range: white.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: microscopic crystals.
Often confused with
Nahpoite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside nahpoite
Minerals reported to co-occur with nahpoite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Na₂HPO₄
- Mohs hardness
- 1-3
- Density
- 2.58 g/cm³
- Colors
- Streak
- White
- Luster
- Dull
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Microscopic crystals
- Cleavage
- Good on {100}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- An alteration product of marićite in nodules in phosphatic ironstone (Yukon Territory, Canada); in sodalite xenoliths associated with an intrusive alkalic gabbro-syenite complex (Mont Saint-Hilaire, Canada)
Where rockhounds find nahpoite
Classic worldwide localities
- Big Fish River area, Yukon Territory, and at Mont Saint-Hilaire, Quebec, Canada
- Mt. Karnasurt, Lovozero massif and on Mt. Rasvumchorr, Khibiny massif, Kola Peninsula, Russia
Field-hunting tip
Where it forms: An alteration product of marićite in nodules in phosphatic ironstone (Yukon Territory, Canada); in sodalite xenoliths associated with an intrusive alkalic gabbro-syenite complex (Mont Saint-Hilaire, Canada). If you start seeing marićite, natrophosphate, villiaumite in float, you are in the right ground. Typical habit: microscopic crystals. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify nahpoite?+
Where is nahpoite found?+
What rocks look like nahpoite?+
What minerals are found with nahpoite?+
What kind of rock does nahpoite form in?+
What is nahpoite used for?+
Find nahpoite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
