Trilithionite is a lithium-rich mica belonging to the lepidolite series. It occurs primarily in complex pegmatites and is often visually indistinguishable from other lepidolite-group micas without chemical analysis, typically presenting as small, scaly, micaceous plates.

Hardness

2.5-3

Mohs

Luster

Pearly

Streak

White

Transparency

Transparent

mineralrareLepidolite family

Trilithionite

Hardness: 2.5-3
Luster: Pearly
Streak: White
Transparency: Transparent

Is this trilithionite?

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 trilithionite with a known reference. Trilithionite sits at Mohs 2.5-3, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Trilithionite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Trilithionite typically shows a pearly luster.
4
Match the color range
Compare against the expected color range: pink, violet, purple, white, colorless.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: tabular crystals, scaly aggregates, massive.

Often confused with

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

Often found alongside trilithionite

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

All properties

Chemical formula: KLi₂Al(AlSi₃)O₁₀(F,OH)₂
Mohs hardness: 2.5-3
Density: 2.8-3.0 g/cm³
Colors: Pink Violet Purple White Colorless
Streak: White
Luster: Pearly
Transparency: Transparent
Crystal system: Monoclinic
Crystal habit: Tabular Crystals, Scaly Aggregates, Massive
Cleavage: Perfect Basal
Rarity: Rare
Uses: Collector
Host rock: Granite Pegmatites
Typical price: $20-150 per specimen

Where rockhounds find trilithionite

Classic worldwide localities

Hagendorf, Germany
Varuträsk, Sweden
Tanco Mine, Canada

Field-hunting tip

Look in granite pegmatites country, the host setting where trilithionite typically forms. If you start seeing quartz, albite, microcline in float, you are in the right ground. Field specimens usually show a tabular crystals, scaly aggregates, massive habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify trilithionite?+

Mohs hardness is 2.5-3. It typically shows a pearly luster. The streak is white. Common colors include pink, violet, purple, white.

Where is trilithionite found?+

Notable localities include Hagendorf, Germany; Varuträsk, Sweden; Tanco Mine, Canada.

How much is trilithionite worth?+

Typical asking prices fall in the range of $20-150 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like trilithionite?+

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

What minerals are found with trilithionite?+

Trilithionite commonly co-occurs with Quartz, Albite, Microcline, Tourmaline, Amblygonite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does trilithionite form in?+

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

What is trilithionite used for?+

Trilithionite is used in collector.

Find trilithionite on the map

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