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
5-6
Mohs
Luster
Vitreous
Streak
White
Transparency
Translucent

Is this takanawaite-(y)?

5-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 5-6 — softer than the next harder reference, harder than the previous one.
  • 2
    Check the streak
    Drag the specimen across an unglazed porcelain plate. Takanawaite-(Y) leaves a white streak.
  • 3
    Read the luster
    Hold the specimen under a strong light. Takanawaite-(Y) typically shows a vitreous luster.
  • 4
    Match the color range
    Compare against the expected color range: yellow, brown, white.
  • 5
    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
5-6
Density
5.68 g/cm³
Streak
White
Luster
Vitreous
Transparency
Translucent
Crystal system
Monoclinic
Crystal habit
Granular to Massive
Cleavage
None
Rarity
Rare
Uses
Collector
Host rock
Granite Pegmatites
Typical price
$50-300+ depending on size and quality

Where rockhounds find takanawaite-(y)

Classic worldwide localities

  • Takanawa Mountain, Ehime Prefecture, Japan

Field-hunting tip

Look in granite pegmatites country — that is the host setting where takanawaite-(y) typically forms. If you start seeing albite, quartz, muscovite in float, you are in the right ground. Field specimens usually show a granular to massive habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify takanawaite-(y)?+
Mohs hardness is 5-6. It typically shows a vitreous luster. The streak is white. Common colors include yellow, brown, white.
Where is takanawaite-(y) found?+
Notable localities include Takanawa Mountain, Ehime Prefecture, Japan.
How much is takanawaite-(y) worth?+
Typical asking prices fall in the range of $50-300+ depending on size and quality. Quality, size, and provenance can move individual specimens well outside that range.
Is takanawaite-(y) safe to handle?+
This mineral is radioactive. Contains yttrium and tantalum, and is frequently radioactive due to trace thorium impurities; handle with care and wash hands after handling specimens. Handle with care, avoid grinding or breathing dust, and store separately.
What minerals are found with takanawaite-(y)?+
Takanawaite-(Y) commonly co-occurs with Albite, Quartz, Muscovite, Garnet. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does takanawaite-(y) form in?+
Takanawaite-(Y) typically forms in granite pegmatites. 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

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.

Download on the App StoreGet it on Google Play