Mongolite is a very rare phyllosilicate mineral that typically forms as delicate, platy crystals or pseudohexagonal clusters. It is primarily found in hydrothermal veins, where it appears as small, pearly-white aggregates that are highly prized by systematic mineral collectors.

Hardness

Mohs

Luster

Pearly

Streak

White

Transparency

Translucent

mineralrare

Mongolite

Hardness: 2
Luster: Pearly
Streak: White
Transparency: Translucent

Is this mongolite?

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 mongolite with a known reference. Mongolite sits at Mohs 2 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Mongolite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Mongolite typically shows a pearly luster.
4
Match the color range
Compare against the expected color range: white, pale yellow.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: platy crystals, pseudohexagonal rosettes, aggregates.

Often confused with

Mongolite vs. its common look-alikes — and how to tell them apart in the field.

mineral

Apophyllite

Mohs 4.5-5

How to tell apart: Apophyllite is the harder of the two (Mohs 4.5-5 vs. 2); luster reads pearly on Mongolite and vitreous to pearly on Apophyllite.

How to tell apart: Gyrolite is the harder of the two (Mohs 3-4 vs. 2).

Compare →

Often found alongside mongolite

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

All properties

Chemical formula: Ca₄(Si₈O₂₀)(OH)₂·12H₂O
Mohs hardness: 2
Density: 2.44 g/cm³
Colors: White Pale Yellow
Streak: White
Luster: Pearly
Transparency: Translucent
Crystal system: Monoclinic
Crystal habit: Platy Crystals, Pseudohexagonal Rosettes, Aggregates
Cleavage: Perfect Basal
Rarity: Rare
Uses: Collector
Host rock: Hydrothermal Veins
Typical price: $50-300 per specimen

Where rockhounds find mongolite

Classic worldwide localities

Mongolia
Russia

Field-hunting tip

Look in hydrothermal veins country — that is the host setting where mongolite typically forms. If you start seeing quartz, adularia, calcite in float, you are in the right ground. Field specimens usually show a platy crystals, pseudohexagonal rosettes, aggregates habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify mongolite?+

Mohs hardness is 2. It typically shows a pearly luster. The streak is white. Common colors include white, pale yellow.

Where is mongolite found?+

Notable localities include Mongolia; Russia.

How much is mongolite worth?+

Typical asking prices fall in the range of $50-300 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like mongolite?+

Mongolite is most often confused with Apophyllite, Gyrolite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with mongolite?+

Mongolite commonly co-occurs with quartz, adularia, calcite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does mongolite form in?+

Mongolite typically forms in hydrothermal veins. Working float back to the host body is the standard way to chase a fresh occurrence.

What is mongolite used for?+

Mongolite is used in collector.

Find mongolite on the map

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