Clinofergusonite-(Nd) is a rare rare-earth niobate mineral typically found in highly evolved alkaline pegmatites. It forms small, dark prismatic crystals that often exhibit a submetallic luster and are frequently radioactive due to trace thorium content.

Hardness

5.5-6.5

Mohs

Luster

Submetallic

Streak

Pale Yellow

Transparency

Opaque

mineralrareFergusonite Group family

Clinofergusonite-(Nd)

Hardness: 5.5-6.5
Luster: Submetallic
Streak: Pale Yellow
Transparency: Opaque

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Is this clinofergusonite-(nd)?

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 clinofergusonite-(nd) with a known reference. Clinofergusonite-(Nd) sits at Mohs 5.5-6.5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Clinofergusonite-(Nd) leaves a pale yellow streak.
3
Read the luster
Hold the specimen under a strong light. Clinofergusonite-(Nd) typically shows a submetallic luster.
4
Match the color range
Compare against the expected color range: yellow, brown, black.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: prismatic crystals.

Often confused with

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

mineral

Fergusonite-(Y)

Mohs 5.5-6.5

How to tell apart: Luster reads submetallic on Clinofergusonite-(Nd) and vitreous on Fergusonite-(Y).

How to tell apart: Streak differs — Clinofergusonite-(Nd) leaves pale yellow, Samarskite-(Y) leaves dark brown.

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Often found alongside clinofergusonite-(nd)

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

All properties

Chemical formula: NdNbO₄
Mohs hardness: 5.5-6.5
Density: 5.6-5.8 g/cm³
Colors: Yellow Brown Black
Streak: Pale Yellow
Luster: Submetallic
Transparency: Opaque
Crystal system: Monoclinic
Crystal habit: Prismatic Crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Alkaline Pegmatites
Typical price: $50-300 per specimen

Where rockhounds find clinofergusonite-(nd)

Classic worldwide localities

Kola Peninsula, Russia
Norra Kärr, Sweden
Mount Malosa, Malawi

Field-hunting tip

Look in alkaline pegmatites country — that is the host setting where clinofergusonite-(nd) typically forms. If you start seeing aegirine, microcline, nepheline in float, you are in the right ground. Field specimens usually show a prismatic crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify clinofergusonite-(nd)?+

Mohs hardness is 5.5-6.5. It typically shows a submetallic luster. The streak is pale yellow. Common colors include yellow, brown, black.

Where is clinofergusonite-(nd) found?+

Notable localities include Kola Peninsula, Russia; Norra Kärr, Sweden; Mount Malosa, Malawi.

How much is clinofergusonite-(nd) 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 clinofergusonite-(nd) safe to handle?+

This mineral is radioactive. Contains rare earth elements and naturally occurring thorium/uranium impurities; avoid inhalation of dust and handle with caution. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like clinofergusonite-(nd)?+

Clinofergusonite-(Nd) is most often confused with Fergusonite-(Y), Samarskite-(Y). A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with clinofergusonite-(nd)?+

Clinofergusonite-(Nd) commonly co-occurs with aegirine, microcline, nepheline, zircon. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does clinofergusonite-(nd) form in?+

Clinofergusonite-(Nd) typically forms in alkaline pegmatites. Working float back to the host body is the standard way to chase a fresh occurrence.

What is clinofergusonite-(nd) used for?+

Clinofergusonite-(Nd) is used in collector.

Find clinofergusonite-(nd) on the map

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