Nanpingite is a rare cesium-rich mica typically found as small, platy inclusions or aggregates within highly evolved pegmatites. Because it closely resembles common muscovite, it is often identified primarily through chemical analysis or specialized X-ray diffraction in geological research settings.

Hardness

2.5

Mohs

Luster

Pearly

Streak

White

Transparency

Transparent

mineralrareMica Group family

Nanpingite

Hardness: 2.5
Luster: Pearly
Streak: White
Transparency: Transparent

Is this nanpingite?

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 nanpingite with a known reference. Nanpingite sits at Mohs 2.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Nanpingite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Nanpingite typically shows a pearly luster.
4
Match the color range
Compare against the expected color range: colorless, white, pale yellow.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: platy or micaceous aggregates.

Often confused with

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

Often found alongside nanpingite

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

All properties

Chemical formula: Cs(AlMg)₂Si₃AlO₁₀(OH)₂
Mohs hardness: 2.5
Density: 3.01 g/cm³
Colors: Colorless White Pale Yellow
Streak: White
Luster: Pearly
Transparency: Transparent
Crystal system: Monoclinic
Crystal habit: Platy or Micaceous Aggregates
Cleavage: Perfect Basal
Rarity: Rare
Uses: Collector
Host rock: Granite Pegmatites
Typical price: $50-300 per specimen

Where rockhounds find nanpingite

Classic worldwide localities

Nanping, Fujian Province, China
Tanco Mine, Manitoba, Canada

Field-hunting tip

Look in granite pegmatites country, the host setting where nanpingite typically forms. If you start seeing quartz, albite, pollucite in float, you are in the right ground. Field specimens usually show a platy or micaceous aggregates habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify nanpingite?+

Mohs hardness is 2.5. It typically shows a pearly luster. The streak is white. Common colors include colorless, white, pale yellow.

Where is nanpingite found?+

Notable localities include Nanping, Fujian Province, China; Tanco Mine, Manitoba, Canada.

How much is nanpingite 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 nanpingite?+

Nanpingite is most often confused with Muscovite, Polylithionite, Lepidolite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with nanpingite?+

Nanpingite commonly co-occurs with Quartz, Albite, Pollucite, Spodumene. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does nanpingite form in?+

Nanpingite typically forms in granite pegmatites. Working float back to the host body is the standard way to chase a fresh occurrence.

What is nanpingite used for?+

Nanpingite is used in collector.

Find nanpingite on the map

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