Mäkinenite is a rare hexagonal modification of elemental selenium that typically occurs as metallic, dark-colored platy crystals or masses. It is primarily found in hydrothermal environments associated with selenium-bearing sulfide ores, making it a sought-after rarity for advanced mineral collectors.

Hardness

2.5-3

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrare

Mäkinenite

Hardness: 2.5-3
Luster: Metallic
Streak: Black
Transparency: Opaque

Is this mäkinenite?

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 mäkinenite with a known reference. Mäkinenite sits at Mohs 2.5-3, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Streak: black.
3
Read the luster
Hold the specimen under a strong light. Luster: metallic.
4
Match the color range
Compare against the expected color range: yellow, orange yellow.
5
Look at form & habit
Crystal system: trigonal. Typical habit: massive.

Often confused with

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

How to tell apart: Mäkinenite is noticeably harder (Mohs 2.5-3 vs. 1-1.5); streak differs, so Mäkinenite leaves black, Molybdenite leaves bluish gray.

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Often found alongside mäkinenite

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

Clausthalite
mineral · Mohs 2.5-3

All properties

Chemical formula: NiSe
Mohs hardness: 2.5-3
Density: 7.22 g/cm³
Colors: Yellow Orange yellow
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Trigonal
Crystal habit: Massive
Cleavage: Perfect
Rarity: Rare
Uses: Collector
Host rock: In sills of albite diabase in schist, associated with low-grade uranium mineralization (Kuusamo, Finland)

Where rockhounds find mäkinenite

Classic worldwide localities

Finland, from Kuusamo (type locality) and Hitura

Field-hunting tip

Where it forms: In sills of albite diabase in schist, associated with low-grade uranium mineralization (Kuusamo, Finland). If you start seeing clausthalite, selenian melonite in float, you are in the right ground. Typical habit: massive. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify mäkinenite?+

Mohs hardness is 2.5-3. Luster: metallic. The streak is black. Common colors include yellow, orange yellow.

Where is mäkinenite found?+

Notable localities include Finland, from Kuusamo (type locality) and Hitura.

Is mäkinenite safe to handle?+

Mäkinenite contains nickel and selenium. Mäkinenite contains selenium, which is toxic if ingested or inhaled as dust. Wash hands thoroughly after handling specimens.

What rocks look like mäkinenite?+

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

What minerals are found with mäkinenite?+

Mäkinenite commonly co-occurs with Clausthalite, Selenian melonite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does mäkinenite form in?+

Where it forms: In sills of albite diabase in schist, associated with low-grade uranium mineralization (Kuusamo, Finland). Working float back to the host body is the standard way to chase a fresh occurrence.

What is mäkinenite used for?+

Mäkinenite is used in collector.

Find mäkinenite on the map

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