Trolleite is a rare phosphate mineral often found in high-pressure metamorphic environments. It typically appears as pale blue-green or white massive aggregates, frequently associated with other aluminum phosphates like lazulite and augelite.

Hardness

5.5-6

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrare

Trolleite

Hardness: 5.5-6
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this trolleite?

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 trolleite with a known reference. Trolleite sits at Mohs 5.5-6 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Trolleite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Trolleite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: pale green, blue-green, white, colorless.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: massive, granular, rarely as small pseudo-hexagonal crystals.

Often confused with

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

How to tell apart: Trolleite is noticeably harder (Mohs 5.5-6 vs. 3.5-4.5); luster reads vitreous on Trolleite and waxy on Variscite.

Compare →

Often found alongside trolleite

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

All properties

Chemical formula: Al₄(PO₄)₃(OH)₃
Mohs hardness: 5.5-6
Density: 3.10 g/cm³
Colors: Pale Green Blue-green White Colorless
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Monoclinic
Crystal habit: Massive, Granular, Rarely as Small Pseudo-hexagonal Crystals
Cleavage: Distinct On {110}
Rarity: Rare
Uses: Collector, Lapidary
Host rock: Metamorphic Rocks Rich in Aluminum and Phosphorus
Typical price: $20-150 for small specimens, higher for gem-grade rough

Where rockhounds find trolleite

Classic worldwide localities

Västanå mine, Sweden
Rapid Creek, Yukon, Canada
Champion mine, California, USA
Minas Gerais, Brazil

Field-hunting tip

Look in metamorphic rocks rich in aluminum and phosphorus country — that is the host setting where trolleite typically forms. If you start seeing augelite, attakolite, lazulite in float, you are in the right ground. Field specimens usually show a massive, granular, rarely as small pseudo-hexagonal crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify trolleite?+

Mohs hardness is 5.5-6. It typically shows a vitreous luster. The streak is white. Common colors include pale green, blue-green, white, colorless.

Where is trolleite found?+

Notable localities include Västanå mine, Sweden; Rapid Creek, Yukon, Canada; Champion mine, California, USA; Minas Gerais, Brazil.

How much is trolleite worth?+

Typical asking prices fall in the range of $20-150 for small specimens, higher for gem-grade rough. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like trolleite?+

Trolleite is most often confused with Lazulite, Scorzalite, Variscite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with trolleite?+

Trolleite commonly co-occurs with Augelite, Attakolite, Lazulite, Quartz, Kyanite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does trolleite form in?+

Trolleite typically forms in metamorphic rocks rich in aluminum and phosphorus. Working float back to the host body is the standard way to chase a fresh occurrence.

What is trolleite used for?+

Trolleite is used in collector, lapidary.

Find trolleite on the map

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