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, 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, 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
- 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
- A late-stage product possibly related to the in situ alteration of the pre-existing mineral assemblage present in the core of a zoned peralkaline pegmatite dike encased in a hornfels xenolith
Where rockhounds find peatite-(y)
Classic worldwide localities
- Poudrette pegmatite, Mont Saint-Hilaire, La Vallée-du-Richelieu, Montérégie (formerly Rouville County), Québec, Canada
Field-hunting tip
Where it forms: A late-stage product possibly related to the in situ alteration of the pre-existing mineral assemblage present in the core of a zoned peralkaline pegmatite dike encased in a hornfels xenolith. If you start seeing ramikite-, albite, rhodochrosite in float, you are in the right ground. Typical habit: fibrous, earthy, massive. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify peatite-(y)?+
Where is peatite-(y) found?+
What rocks look like peatite-(y)?+
What minerals are found with peatite-(y)?+
What kind of rock does peatite-(y) form in?+
What is peatite-(y) used for?+
Find peatite-(y) on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
