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, 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.