Yttrocrasite-(Y) is a rare yttrium-rich titano-niobate mineral that typically occurs as massive, opaque black grains. It is primarily found within granite pegmatites and is highly valued by radioactive mineral collectors due to its complex chemical composition and scarcity.

Hardness
5.5-6
Mohs
Luster
Resinous
Streak
Yellowish Brown
Transparency
Opaque

Is this yttrocrasite-(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 yttrocrasite-(y) with a known reference. Yttrocrasite-(Y) sits at Mohs 5.5-6 — softer than the next harder reference, harder than the previous one.
  • 2
    Check the streak
    Drag the specimen across an unglazed porcelain plate. Yttrocrasite-(Y) leaves a yellowish brown streak.
  • 3
    Read the luster
    Hold the specimen under a strong light. Yttrocrasite-(Y) typically shows a resinous luster.
  • 4
    Match the color range
    Compare against the expected color range: black, brownish black.
  • 5
    Look at form & habit
    Crystal system: orthorhombic. Typical habit: massive, anhedral grains.

Often confused with

Yttrocrasite-(Y) vs. its common look-alikes — and how to tell them apart in the field.

Often found alongside yttrocrasite-(y)

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

All properties

Chemical formula
(Y,Th,Ca,U)(Ti,Fe)₂(O,OH)₆
Mohs hardness
5.5-6
Density
4.8 g/cm³
Streak
Yellowish Brown
Luster
Resinous
Transparency
Opaque
Crystal system
Orthorhombic
Crystal habit
Massive, Anhedral Grains
Cleavage
None
Rarity
Rare
Uses
Collector
Host rock
Granite Pegmatites
Typical price
$50-300 per specimen

Where rockhounds find yttrocrasite-(y)

Classic worldwide localities

  • Burnet County, Texas, USA
  • Madagascar
  • Norway

Field-hunting tip

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

Common questions

How do you identify yttrocrasite-(y)?+
Mohs hardness is 5.5-6. It typically shows a resinous luster. The streak is yellowish brown. Common colors include black, brownish black.
Where is yttrocrasite-(y) found?+
Notable localities include Burnet County, Texas, USA; Madagascar; Norway.
How much is yttrocrasite-(y) worth?+
Typical asking prices fall in the range of $50-300 per specimen. Quality, size, and provenance can move individual specimens well outside that range.
Is yttrocrasite-(y) safe to handle?+
This mineral is radioactive. Contains thorium and uranium; radioactive, requires safe handling, storage, and should not be kept in close proximity to living spaces or other sensitive materials. Handle with care, avoid grinding or breathing dust, and store separately.
What rocks look like yttrocrasite-(y)?+
Yttrocrasite-(Y) is most often confused with Euxenite. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with yttrocrasite-(y)?+
Yttrocrasite-(Y) commonly co-occurs with Allanite, Quartz, Microcline, Biotite. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does yttrocrasite-(y) form in?+
Yttrocrasite-(Y) typically forms in granite pegmatites. Working float back to the host body is the standard way to chase a fresh occurrence.
What is yttrocrasite-(y) used for?+
Yttrocrasite-(Y) is used in collector.

Find yttrocrasite-(y) on the map

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