Kvanefjeldite is a rare phyllosilicate mineral found primarily in the unique agpaitic rocks of the Ilimaussaq complex in Greenland. It is highly valued by collectors for its brilliant white fluorescence under short-wave ultraviolet light and its tight association with other exotic alkaline minerals.

Hardness

3-4

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrarenull family

Kvanefjeldite

Hardness: 3-4
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this kvanefjeldite?

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 kvanefjeldite with a known reference. Kvanefjeldite sits at Mohs 3-4 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Kvanefjeldite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Kvanefjeldite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: pink, brown, white.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: tabular crystals, massive, granular.

Often confused with

Kvanefjeldite vs. its common look-alikes — and how to tell them apart in the field.

mineral

Eudialyte

Mohs 5-6

How to tell apart: Eudialyte is the harder of the two (Mohs 5-6 vs. 3-4).

How to tell apart: Streak differs — Kvanefjeldite leaves white, Steenstrupine-(Ce) leaves yellowish brown.

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Often found alongside kvanefjeldite

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

All properties

Chemical formula: Na₄(Mn,Fe)Si₄O₁₀·H₂O
Mohs hardness: 3-4
Density: 2.44 g/cm³
Colors: Pink Brown White
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Orthorhombic
Crystal habit: Tabular Crystals, Massive, Granular
Cleavage: Perfect
Fluorescence: Bright White Under SW UV
Rarity: Rare
Uses: Collector
Host rock: Agpaitic Nepheline Syenites
Typical price: $50-300 per specimen

Where rockhounds find kvanefjeldite

Classic worldwide localities

Ilimaussaq Complex, Greenland

Field-hunting tip

Look in agpaitic nepheline syenites country — that is the host setting where kvanefjeldite typically forms. If you start seeing eudialyte, steenstrupine-(ce), arfvedsonite in float, you are in the right ground. Field specimens usually show a tabular crystals, massive, granular habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify kvanefjeldite?+

Mohs hardness is 3-4. It typically shows a vitreous luster. The streak is white. Common colors include pink, brown, white.

Where is kvanefjeldite found?+

Notable localities include Ilimaussaq Complex, Greenland.

How much is kvanefjeldite 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 kvanefjeldite safe to handle?+

This mineral is radioactive. Kvanefjeldite contains radioactive elements (often associated with eudialyte and steenstrupine) and should be stored in a labeled, lead-lined, or sealed container to minimize exposure. Wash hands thoroughly after handling. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like kvanefjeldite?+

Kvanefjeldite is most often confused with Eudialyte, Steenstrupine-(Ce). A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with kvanefjeldite?+

Kvanefjeldite commonly co-occurs with Eudialyte, Steenstrupine-(Ce), Arfvedsonite, Microcline, Nepheline. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does kvanefjeldite form in?+

Kvanefjeldite typically forms in agpaitic nepheline syenites. Working float back to the host body is the standard way to chase a fresh occurrence.

What is kvanefjeldite used for?+

Kvanefjeldite is used in collector.

Find kvanefjeldite on the map

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