Peatite-(Y) is a rare lithium sodium yttrium phosphate, typically colorless. It was approved as a distinct mineral species in 2009. It was first described from the Poudrette pegmatite, Montérégie (formerly Rouville County), Québec, Canada.
Is this peatite-(y)?
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 peatite-(y) with a known reference. Peatite-(Y) sits at Mohs 3-4, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Peatite-(Y) leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Peatite-(Y) typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: colorless, pale pink, purple.
- 5Look at form & habitCrystal system: orthorhombic. Typical habit: fibrous, earthy, massive.
Often confused with
Peatite-(Y) vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside peatite-(y)
Minerals reported to co-occur with peatite-(y). Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Li₄Na₁₂(Y,Na,Ca,REE)₁₂(PO₄)₁₂(CO₃)₄(F,OH)₈
- Mohs hardness
- 3-4
- Density
- 3.62 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Orthorhombic
- Crystal habit
- Fibrous, Earthy, Massive
- Cleavage
- Very Good On {100}, {010}, {001}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Granite Pegmatites
Where rockhounds find peatite-(y)
Classic worldwide localities
- Sweden
- USA
- Norway
- Canada
Field-hunting tip
Look in granite pegmatites country, the host setting where peatite-(y) typically forms. If you start seeing allanite, gadolinite, fluorite in float, you are in the right ground. Field specimens usually show a fibrous, earthy, massive habit, so train your eye for that shape before scanning the outcrop.







