Lusernaite-(Y) is an extremely rare yttrium-aluminum carbonate mineral first discovered in the granite pegmatites of Luserna, Italy. It typically forms as small, delicate tabular crystals or radiating sprays within pockets of altered feldspar. Collectors value it for its high yttrium content and its unique status as a specific type locality mineral.
Is this lusernaite-(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 lusernaite-(y) with a known reference. Lusernaite-(Y) sits at Mohs 4, 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: pearly.
- 4Match the color rangeCompare against the expected color range: colorless.
- 5Look at form & habitCrystal system: orthorhombic. Typical habit: tabular crystals, radiating aggregates.
Often confused with
Lusernaite-(Y) vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside lusernaite-(y)
Minerals reported to co-occur with lusernaite-(y). Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Y₄Al(CO₃)₂(OH)₁₁(H₂O)₄·2H₂O
- Mohs hardness
- 4
- Density
- 2.810 g/cm³
- Colors
- Streak
- White
- Luster
- Pearly
- Transparency
- Transparent
- Crystal system
- Orthorhombic
- Crystal habit
- Tabular crystals, radiating aggregates
- Cleavage
- Perfect on {010}, less perfect on {100}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A late-stage hydrothermal mineral in fractures in regionally metamorphosed gneiss
Where rockhounds find lusernaite-(y)
Classic worldwide localities
- Seccarezze quarries, Luserna San Giovanni, Torino, Piedmont, Italy
Field-hunting tip
Where it forms: A late-stage hydrothermal mineral in fractures in regionally metamorphosed gneiss. If you start seeing aeschynite-, albite, chlorite in float, you are in the right ground. Typical habit: tabular crystals, radiating aggregates. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify lusernaite-(y)?+
Where is lusernaite-(y) found?+
What rocks look like lusernaite-(y)?+
What minerals are found with lusernaite-(y)?+
What kind of rock does lusernaite-(y) form in?+
What is lusernaite-(y) used for?+
Find lusernaite-(y) on the map
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