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.
Is this treasurite?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch treasurite with a known reference. Treasurite sits at Mohs 3.5 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Treasurite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Treasurite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: colorless, white, gray.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: tabular crystals.
Often confused with
Treasurite vs. its common look-alikes — and how to tell them apart in the field.
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
- 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 — that is 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.




