Adamsite-(Y) is an exceptionally rare yttrium carbonate mineral found almost exclusively in the alkaline igneous complexes of Mont Saint-Hilaire. It typically appears as delicate, colorless to pale yellow platy crystals often arranged in radiating or rosette-like clusters. Due to its scarcity and fragile nature, it is highly sought after by advanced systematic mineral collectors.
Is this adamsite-(y)?
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 adamsite-(y) with a known reference. Adamsite-(Y) sits at Mohs 3, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous to pearly.
- 4Match the color rangeCompare against the expected color range: white, colorless, pale pink, pale purple.
- 5Look at form & habitCrystal system: triclinic. Typical habit: aggregates, radial, spherical.
Often confused with
Adamsite-(Y) vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside adamsite-(y)
Minerals reported to co-occur with adamsite-(y). Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- NaY(CO₃)₂·6H₂O
- Mohs hardness
- 3
- Density
- 2.27 g/cm³
- Streak
- White
- Luster
- Vitreous to pearly
- Transparency
- Transparent to translucent
- Crystal system
- Triclinic
- Crystal habit
- Aggregates, radial, spherical
- Cleavage
- Perfect on {001}; good on {100}, {010}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A rare late-stage, low-temperature hydrothermal mineral in an alkalic pegmatite dike associated with an intrusive alkalic gabbro-syenite complex
Where rockhounds find adamsite-(y)
Classic worldwide localities
- Mont Saint-Hilaire, Quebec, Canada
Field-hunting tip
Where it forms: A rare late-stage, low-temperature hydrothermal mineral in an alkalic pegmatite dike associated with an intrusive alkalic gabbro-syenite complex. If you start seeing thomasclarkite-, horváthite-, donnayite- in float, you are in the right ground. Typical habit: aggregates, radial, spherical. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify adamsite-(y)?+
Where is adamsite-(y) found?+
What rocks look like adamsite-(y)?+
What minerals are found with adamsite-(y)?+
What kind of rock does adamsite-(y) form in?+
What is adamsite-(y) used for?+
Find adamsite-(y) on the map
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