Lun'okite is a rare manganese aluminum phosphate mineral found primarily in granitic pegmatites. It typically occurs as small, delicate prismatic crystals or radial sprays in association with other phosphate minerals.

Hardness

3-4

Mohs

Luster

Vitreous

Streak

White

Transparency

Semitransparent

mineralrareHopeite Group family

Lun'okite

Hardness: 3-4
Luster: Vitreous
Streak: White
Transparency: Semitransparent

Is this lun'okite?

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 lun'okite with a known reference. Lun'okite 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. Streak: white.
3
Read the luster
Hold the specimen under a strong light. Luster: vitreous.
4
Match the color range
Compare against the expected color range: white, colorless.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: acicular, aggregates, radial.

Often confused with

Lun'okite vs. its common look-alikes, and how to tell them apart in the field.

Often found alongside lun'okite

Minerals reported to co-occur with lun'okite. Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula: MgMnAl(PO₄)₂(OH)(H₂O)₄
Mohs hardness: 3-4
Density: 2.66 g/cm³
Colors: White Colorless
Streak: White
Luster: Vitreous
Transparency: Semitransparent
Crystal system: Orthorhombic
Crystal habit: Acicular, aggregates, radial
Cleavage: Perfect on {010}; imperfect on {001}
Rarity: Rare
Uses: Collector
Host rock: In fractures and on crusts of mitridatite in granite pegmatites

Where rockhounds find lun'okite

Classic worldwide localities

Mt. Vasin-Myl’k, Voron’i massif, Kola Peninsula, Russia

Field-hunting tip

Where it forms: In fractures and on crusts of mitridatite in granite pegmatites. If you start seeing eosphorite, laueite, kingsmountite in float, you are in the right ground. Typical habit: acicular, aggregates, radial. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify lun'okite?+

Mohs hardness is 3-4. Luster: vitreous. The streak is white. Common colors include white, colorless.

Where is lun'okite found?+

Notable localities include Mt. Vasin-Myl’k, Voron’i massif, Kola Peninsula, Russia.

What rocks look like lun'okite?+

Lun'okite is most often confused with Hopeite, Parahopeite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with lun'okite?+

Lun'okite commonly co-occurs with Eosphorite, Laueite, Kingsmountite, Fairfieldite, Mitridatite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does lun'okite form in?+

Where it forms: In fractures and on crusts of mitridatite in granite pegmatites. Working float back to the host body is the standard way to chase a fresh occurrence.

What is lun'okite used for?+

Lun'okite is used in collector.

Find lun'okite on the map

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