Waimirite-(Y) is a very rare yttrium fluoride mineral discovered in Amazonian granitic pegmatites. It typically occurs as small, clear, platy crystals often found in association with other rare-element pegmatite minerals.
Is this waimirite-(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 waimirite-(y) with a known reference. Waimirite-(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. Waimirite-(Y) leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Waimirite-(Y) typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: colorless, white.
- 5Look at form & habitCrystal system: trigonal. Typical habit: platy crystals.
Often confused with
Waimirite-(Y) vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside waimirite-(y)
Minerals reported to co-occur with waimirite-(y). Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- YF₃
- Mohs hardness
- 4
- Density
- 5.71 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Trigonal
- Crystal habit
- Platy Crystals
- Cleavage
- Distinct On {0001}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Rare-element Granitic Pegmatites
- Typical price
- expensive
Where rockhounds find waimirite-(y)
Classic worldwide localities
- Waimiri-Atroari, Amazonas, Brazil
Field-hunting tip
Look in rare-element granitic pegmatites country — that is the host setting where waimirite-(y) typically forms. If you start seeing quartz, microcline, albite in float, you are in the right ground. Field specimens usually show a platy crystals habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify waimirite-(y)?+
Where is waimirite-(y) found?+
How much is waimirite-(y) worth?+
What rocks look like waimirite-(y)?+
What minerals are found with waimirite-(y)?+
What kind of rock does waimirite-(y) form in?+
What is waimirite-(y) used for?+
Find waimirite-(y) on the map
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