Micheelsenite is an extremely rare phosphate mineral known primarily from the Mont Saint-Hilaire alkaline complex. Collectors prize it for its delicate, acicular, and radiating crystal habits found within cavities of syenite pegmatites.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrare

Micheelsenite

Hardness: 3
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this micheelsenite?

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 micheelsenite with a known reference. Micheelsenite sits at Mohs 3 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Micheelsenite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Micheelsenite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: colorless, white, pale blue.
5
Look at form & habit
Crystal system: hexagonal. Typical habit: acicular crystals, radiating clusters.

Often confused with

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

mineral

Tvedalite

Mohs 3-4

How to tell apart: Luster reads vitreous on Micheelsenite and pearly on Tvedalite.

How to tell apart: Gittinsite is the harder of the two (Mohs 5 vs. 3).

Compare →

Often found alongside micheelsenite

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

All properties

Chemical formula: Ca₃Al(PO₄)₂(OH)₅·2H₂O
Mohs hardness: 3
Density: 2.44 g/cm³
Colors: Colorless White Pale Blue
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Hexagonal
Crystal habit: Acicular Crystals, Radiating Clusters
Cleavage: None Observed
Rarity: Rare
Uses: Collector
Host rock: Alkaline Igneous Intrusions
Typical price: $50-300 per specimen

Where rockhounds find micheelsenite

Classic worldwide localities

Poudrette quarry, Mont Saint-Hilaire, Quebec, Canada

Field-hunting tip

Look in alkaline igneous intrusions country — that is the host setting where micheelsenite typically forms. If you start seeing apatite, quartz, albite in float, you are in the right ground. Field specimens usually show a acicular crystals, radiating clusters habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify micheelsenite?+

Mohs hardness is 3. It typically shows a vitreous luster. The streak is white. Common colors include colorless, white, pale blue.

Where is micheelsenite found?+

Notable localities include Poudrette quarry, Mont Saint-Hilaire, Quebec, Canada.

How much is micheelsenite 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 micheelsenite?+

Micheelsenite is most often confused with Tvedalite, Gittinsite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with micheelsenite?+

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

What kind of rock does micheelsenite form in?+

Micheelsenite typically forms in alkaline igneous intrusions. Working float back to the host body is the standard way to chase a fresh occurrence.

What is micheelsenite used for?+

Micheelsenite is used in collector.

Find micheelsenite on the map

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