Treasurite is an exceptionally rare carbonate mineral primarily known from the alkaline igneous complex at Mont Saint-Hilaire. It typically occurs as small, delicate tabular crystals associated with other rare mineral species in vugs and cavities.

Hardness

3.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrare

Treasurite

Hardness: 3.5
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this treasurite?

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 treasurite with a known reference. Treasurite sits at Mohs 3.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Treasurite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Treasurite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: colorless, white, gray.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: tabular crystals.

Often confused with

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

How to tell apart: Luster reads vitreous on Treasurite and pearly on Dawsonite.

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Often found alongside treasurite

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

All properties

Chemical formula: Na₂Ca₄(CO₃)₅
Mohs hardness: 3.5
Density: 2.9-3.0 g/cm³
Colors: Colorless White Gray
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Monoclinic
Crystal habit: Tabular Crystals
Cleavage: Perfect
Rarity: Rare
Uses: Collector
Host rock: Alkaline Igneous Intrusions
Typical price: $50-300 per specimen

Where rockhounds find treasurite

Classic worldwide localities

Mont Saint-Hilaire, Quebec, Canada

Field-hunting tip

Look in alkaline igneous intrusions country, the host setting where treasurite typically forms. If you start seeing analcime, siderite, microcline in float, you are in the right ground. Field specimens usually show a tabular crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify treasurite?+

Mohs hardness is 3.5. It typically shows a vitreous luster. The streak is white. Common colors include colorless, white, gray.

Where is treasurite found?+

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

How much is treasurite 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 treasurite?+

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

What minerals are found with treasurite?+

Treasurite commonly co-occurs with Analcime, Siderite, Microcline. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does treasurite form in?+

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

What is treasurite used for?+

Treasurite is used in collector.

Find treasurite on the map

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