Takanawaite-(Y) is an extremely rare yttrium tantalum oxide mineral that was first identified in the Takanawa Peninsula of Japan. It typically appears as small granular or massive aggregates within granitic pegmatite environments, often associated with other rare earth minerals. Due to its scarcity and radioactivity, it is primarily sought after by advanced systematic mineral collectors.

Hardness

Mohs

Transparency

Translucent

mineralrare

Takanawaite-(Y)

Hardness: 5.5
Transparency: Translucent

No image

Is this takanawaite-(y)?

3-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

1
Test the hardness
Try to scratch takanawaite-(y) with a known reference. Takanawaite-(Y) sits at Mohs 5.5, softer than the next harder reference, harder than the previous one.
2
Match the color range
Compare against the expected color range: dark brown.
3
Look at form & habit
Crystal system: monoclinic. Typical habit: granular to massive.

Often found alongside takanawaite-(y)

Minerals reported to co-occur with takanawaite-(y). Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula: YTaO₄
Mohs hardness: 5.5
Density: 6.97 g/cm³
Colors: Dark brown
Transparency: Translucent
Crystal system: Monoclinic
Crystal habit: Granular to massive
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: In pegmatites in granite

Where rockhounds find takanawaite-(y)

Classic worldwide localities

Takanawa Mountain, near Matsuyama City, Ehime Prefecture, Japan

Field-hunting tip

Where it forms: In pegmatites in granite. If you start seeing gadolinite-, zircon, muscovite in float, you are in the right ground. Typical habit: granular to massive. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify takanawaite-(y)?+

Mohs hardness is 5.5. Common colors include dark brown.

Where is takanawaite-(y) found?+

Notable localities include Takanawa Mountain, near Matsuyama City, Ehime Prefecture, Japan.

Is takanawaite-(y) safe to handle?+

Takanawaite-(Y) contains trace uranium or thorium. Contains yttrium and tantalum, and is frequently radioactive due to trace thorium impurities; handle with care and wash hands after handling specimens.

What minerals are found with takanawaite-(y)?+

Takanawaite-(Y) commonly co-occurs with Gadolinite-, Zircon, Muscovite, Allanite-, Quartz, Feldspar. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does takanawaite-(y) form in?+

Where it forms: In pegmatites in granite. Working float back to the host body is the standard way to chase a fresh occurrence.

What is takanawaite-(y) used for?+

Takanawaite-(Y) is used in collector.

Find takanawaite-(y) on the map

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