Hizenite-(Y) is a rare yttrium-calcium carbonate typically found as a secondary alteration product of other yttrium-bearing minerals in granitic pegmatites. It usually occurs as white, earthy, or fibrous masses and requires mineralogical analysis to distinguish from similar rare-earth carbonates.
Is this hizenite-(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 hizenite-(y) with a known reference. Hizenite-(Y) sits at Mohs 3-4, 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: vitreous to silky.
- 4Match the color rangeCompare against the expected color range: white.
- 5Look at form & habitCrystal system: orthorhombic. Typical habit: massive, aggregates of tiny fibers, microcrystalline.
Often confused with
Hizenite-(Y) vs. its common look-alikes, and how to tell them apart in the field.
All properties
- Chemical formula
- Ca₂Y₆(CO₃)₁₁·14H₂O
- Mohs hardness
- 3-4
- Density
- 2.98 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous to silky
- Transparency
- Transparent to translucent
- Crystal system
- Orthorhombic
- Crystal habit
- Massive, aggregates of tiny fibers, microcrystalline
- Cleavage
- Perfect on {001}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- As a druse in alkali olivine basalt
Where rockhounds find hizenite-(y)
Classic worldwide localities
- Mitsukoshi, Karatsu, Saga Prefecture, Japan
Field-hunting tip
Where it forms: As a druse in alkali olivine basalt. If you start seeing lokkaite-, tengerite-, kimuraite- in float, you are in the right ground. Typical habit: massive, aggregates of tiny fibers, microcrystalline. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify hizenite-(y)?+
Where is hizenite-(y) found?+
What rocks look like hizenite-(y)?+
What minerals are found with hizenite-(y)?+
What kind of rock does hizenite-(y) form in?+
What is hizenite-(y) used for?+
Find hizenite-(y) on the map
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