Yttrocolumbite-(Y) is a rare yttrium-rich niobium-tantalum oxide found primarily in complex granitic pegmatites. It typically appears as dark, resinous, massive material and is often radioactive due to the presence of uranium within its crystal structure.

Hardness

5-5.5

Mohs

Luster

Resinous

Streak

Yellowish

Transparency

Opaque

mineralrareColumbite Group family

Yttrocolumbite-(Y)

Hardness: 5-5.5
Luster: Resinous
Streak: Yellowish
Transparency: Opaque

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

Often confused with

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

mineral

Columbium Ore

Mohs 6

How to tell apart: Streak differs — Yttrocolumbite-(Y) leaves yellowish, Columbium Ore leaves dark red to black; luster reads resinous on Yttrocolumbite-(Y) and submetallic on Columbium Ore.

Compare →

Often found alongside yttrocolumbite-(y)

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

All properties

Chemical formula: (Y,U,Fe)₂(Nb,Ta)₂O₆
Mohs hardness: 5-5.5
Density: 5.5-6.0 g/cm³
Colors: Black Brownish Black Yellowish Brown
Streak: Yellowish
Luster: Resinous
Transparency: Opaque
Crystal system: Orthorhombic
Crystal habit: Massive, Tabular Crystals, Or Crusts
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Granite Pegmatites
Typical price: $50-300 per specimen

Where rockhounds find yttrocolumbite-(y)

Classic worldwide localities

Moss, Norway
Ytterby, Sweden
Iveland, Norway
Kola Peninsula, Russia

Field-hunting tip

Look in granite pegmatites country — that is the host setting where yttrocolumbite-(y) typically forms. If you start seeing feldspar, quartz, mica in float, you are in the right ground. Field specimens usually show a massive, tabular crystals, or crusts habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify yttrocolumbite-(y)?+

Mohs hardness is 5-5.5. It typically shows a resinous luster. The streak is yellowish. Common colors include black, brownish black, yellowish brown.

Where is yttrocolumbite-(y) found?+

Notable localities include Moss, Norway; Ytterby, Sweden; Iveland, Norway; Kola Peninsula, Russia.

How much is yttrocolumbite-(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 yttrocolumbite-(y) safe to handle?+

This mineral is radioactive. Contains uranium and yttrium; emits low-level radiation and should be stored properly in a sealed container, handled with minimal skin contact, and not stored in living or sleeping areas. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like yttrocolumbite-(y)?+

Yttrocolumbite-(Y) is most often confused with Columbium Ore. A quick hardness test and a streak check separate the look-alikes faster than color alone.

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

Yttrocolumbite-(Y) commonly co-occurs with Feldspar, Quartz, Mica, Monazite, Zircon. Spotting any of these in float or country rock is a useful trip signal.

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

Yttrocolumbite-(Y) typically forms in granite pegmatites. Working float back to the host body is the standard way to chase a fresh occurrence.

What is yttrocolumbite-(y) used for?+

Yttrocolumbite-(Y) is used in collector.

Find yttrocolumbite-(y) on the map

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