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, 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.