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.

Hardness
3-4
Mohs
Luster
Vitreous
Streak
White
Transparency
Translucent

Is this peatite-(y)?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

  • 1
    Test the hardness
    Try 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.
  • 2
    Check the streak
    Drag the specimen across an unglazed porcelain plate. Peatite-(Y) leaves a white streak.
  • 3
    Read the luster
    Hold the specimen under a strong light. Peatite-(Y) typically shows a vitreous luster.
  • 4
    Match the color range
    Compare against the expected color range: colorless, pale pink, purple.
  • 5
    Look at form & habit
    Crystal 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.

Common questions

How do you identify peatite-(y)?+
Mohs hardness is 3-4. It typically shows a vitreous luster. The streak is white. Common colors include colorless, pale pink, purple.
Where is peatite-(y) found?+
Notable localities include Sweden; USA; Norway; Canada.
What rocks look like peatite-(y)?+
Peatite-(Y) is most often confused with Tengerite-(Y), Calcite, Hydromagnesite. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with peatite-(y)?+
Peatite-(Y) commonly co-occurs with Allanite, Gadolinite, Fluorite, Quartz. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does peatite-(y) form in?+
Peatite-(Y) typically forms in granite pegmatites. Working float back to the host body is the standard way to chase a fresh occurrence.
What is peatite-(y) used for?+
Peatite-(Y) is used in collector.

Find peatite-(y) on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.

Download on the App StoreGet it on Google Play