Murunskite is a rare potassium-copper-iron sulfide mineral first discovered in the Murun Massif in Siberia. Collectors typically find it as microscopic inclusions or small massive grains within alkaline rock environments rather than as well-formed macro crystals.

Hardness

3-4

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrare

Murunskite

Hardness: 3-4
Luster: Metallic
Streak: Black
Transparency: Opaque

No image

Is this murunskite?

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 murunskite with a known reference. Murunskite 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. Murunskite leaves a black streak.
3
Read the luster
Hold the specimen under a strong light. Murunskite typically shows a metallic luster.
4
Match the color range
Compare against the expected color range: bronze-yellow, steel-gray.
5
Look at form & habit
Crystal system: tetragonal. Typical habit: massive, anhedral grains.

Often confused with

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

mineral

Bornite

Mohs 3

How to tell apart: Streak differs — Murunskite leaves black, Bornite leaves greyish black.

How to tell apart: Streak differs — Murunskite leaves black, Chalcopyrite leaves greenish-black.

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Often found alongside murunskite

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

All properties

Chemical formula: K₂Cu₃FeS₄
Mohs hardness: 3-4
Density: 5.68 g/cm³
Colors: Bronze-yellow Steel-gray
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Tetragonal
Crystal habit: Massive, Anhedral Grains
Cleavage: None
Rarity: Rare
Uses: Collector, Scientific Research
Host rock: Alkaline Igneous Massifs
Typical price: $50-300 per small specimen

Where rockhounds find murunskite

Classic worldwide localities

Murun Massif (Russia)
Udokan copper deposit (Russia)

Field-hunting tip

Look in alkaline igneous massifs country — that is the host setting where murunskite typically forms. If you start seeing potassium-feldspar, charoite, calcite 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 murunskite?+

Mohs hardness is 3-4. It typically shows a metallic luster. The streak is black. Common colors include bronze-yellow, steel-gray.

Where is murunskite found?+

Notable localities include Murun Massif (Russia); Udokan copper deposit (Russia).

How much is murunskite worth?+

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

Is murunskite safe to handle?+

It contains toxic constituents. Contains copper and potentially harmful sulfides. Wash hands thoroughly after handling and avoid inhaling dust. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like murunskite?+

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

What minerals are found with murunskite?+

Murunskite commonly co-occurs with Potassium-feldspar, Charoite, Calcite, Bornite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does murunskite form in?+

Murunskite typically forms in alkaline igneous massifs. Working float back to the host body is the standard way to chase a fresh occurrence.

What is murunskite used for?+

Murunskite is used in collector, scientific research.

Find murunskite on the map

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