Petalite is a lithium-rich silicate mineral primarily found in lithium-bearing pegmatites. It is sought after by collectors for its transparent, gem-quality crystals, though it is often brittle and requires care when handled or faceted.

Hardness

6-6.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineraluncommon

Petalite

Also: Castorite

Hardness: 6-6.5
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this petalite?

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 petalite with a known reference. Petalite sits at Mohs 6-6.5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Petalite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Petalite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: colorless, white, gray, yellow, pink.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: tabular crystals, massive, columnar.

Often confused with

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

Often found alongside petalite

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

All properties

Chemical formula: LiAlSi₄O₁₀
Mohs hardness: 6-6.5
Density: 2.3-2.5 g/cm³
Colors: Colorless White Gray Yellow Pink
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Monoclinic
Crystal habit: Tabular Crystals, Massive, Columnar
Cleavage: Perfect Basal
Fluorescence: Occasionally Orange or Blue Under UV
Rarity: Uncommon
Uses: Gemstone, Collector, Industrial Source of Lithium
Host rock: Granite Pegmatites
Typical price: $10-50 per gram for gem quality

Where rockhounds find petalite

Classic worldwide localities

Uto, Sweden
Bikita, Zimbabwe
Tanco Mine, Canada
Karibib, Namibia
Newry, Maine, USA

Field-hunting tip

Look in granite pegmatites country — that is the host setting where petalite typically forms. If you start seeing spodumene, lepidolite, tourmaline in float, you are in the right ground. Field specimens usually show a tabular crystals, massive, columnar habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify petalite?+

Mohs hardness is 6-6.5. It typically shows a vitreous luster. The streak is white. Common colors include colorless, white, gray, yellow.

Where is petalite found?+

Notable localities include Uto, Sweden; Bikita, Zimbabwe; Tanco Mine, Canada; Karibib, Namibia; Newry, Maine, USA.

How much is petalite worth?+

Typical asking prices fall in the range of $10-50 per gram for gem quality. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like petalite?+

Petalite is most often confused with Spodumene, Danburite, Quartz. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with petalite?+

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

What kind of rock does petalite form in?+

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

What is petalite used for?+

Petalite is used in gemstone, collector, industrial source of lithium.

Find petalite on the map

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