Heftetjernite is a rare beryllium-manganese sulfide mineral belonging to the helvite group. It typically occurs as small, sharp tetrahedral crystals associated with alkaline pegmatites, often found in the Heftetjern locality of Norway.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrareHelvite Group family

Heftetjernite

Hardness: 6
Luster: Vitreous
Streak: White
Transparency: Translucent

No image

Is this heftetjernite?

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 heftetjernite with a known reference. Heftetjernite sits at Mohs 6 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Heftetjernite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Heftetjernite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: brown, yellowish-brown, reddish-brown.
5
Look at form & habit
Crystal system: cubic. Typical habit: tetrahedral crystals.

Often confused with

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

Often found alongside heftetjernite

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

All properties

Chemical formula: Be₃(Mn,Fe)₄Si₃O₁₂S
Mohs hardness: 6
Density: 3.3-3.4 g/cm³
Colors: Brown Yellowish-brown Reddish-brown
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Cubic
Crystal habit: Tetrahedral Crystals
Cleavage: Poor
Rarity: Rare
Uses: Collector
Host rock: Nepheline Syenite Pegmatites
Typical price: $50-300 for small crystals

Where rockhounds find heftetjernite

Classic worldwide localities

Heftetjern, Norway
Kola Peninsula, Russia

Field-hunting tip

Look in nepheline syenite pegmatites country — that is the host setting where heftetjernite typically forms. If you start seeing microcline, quartz, zircon in float, you are in the right ground. Field specimens usually show a tetrahedral crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify heftetjernite?+

Mohs hardness is 6. It typically shows a vitreous luster. The streak is white. Common colors include brown, yellowish-brown, reddish-brown.

Where is heftetjernite found?+

Notable localities include Heftetjern, Norway; Kola Peninsula, Russia.

How much is heftetjernite worth?+

Typical asking prices fall in the range of $50-300 for small crystals. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like heftetjernite?+

Heftetjernite is most often confused with Danalite, Genthelvite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with heftetjernite?+

Heftetjernite commonly co-occurs with Microcline, Quartz, Zircon, Fluorite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does heftetjernite form in?+

Heftetjernite typically forms in nepheline syenite pegmatites. Working float back to the host body is the standard way to chase a fresh occurrence.

What is heftetjernite used for?+

Heftetjernite is used in collector.

Find heftetjernite on the map

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