Haapalaite is a rare layered sulfide-hydroxide mineral that typically forms as small, platy bronze-yellow crystals. It is most frequently identified in nickel-copper sulfide ore bodies where it occurs as an alteration product of primary sulfide minerals like pentlandite.

Hardness

Mohs

Luster

Metallic, strong

Streak

Black

Transparency

Opaque

mineralrareValleriite Group family

Haapalaite

Hardness: 1
Luster: Metallic, strong
Streak: Black
Transparency: Opaque

Is this haapalaite?

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 haapalaite with a known reference. Haapalaite sits at Mohs 1, 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, strong.
4
Match the color range
Compare against the expected color range: bronze red.
5
Look at form & habit
Crystal system: hexagonal. Typical habit: scaly, thin.

Often confused with

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

How to tell apart: Pyrrhotite is the harder of the two (Mohs 3.5-4.5 vs. 1); streak differs, so Haapalaite leaves black, Pyrrhotite leaves dark grayish black.

How to tell apart: Pentlandite is the harder of the two (Mohs 3.5-4 vs. 1); streak differs, so Haapalaite leaves black, Pentlandite leaves pale bronze-brown.

Compare →

Often found alongside haapalaite

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

All properties

Chemical formula: 2[(Fe,Ni)S]·1.61[(Mg,Fe)(OH)₂]
Mohs hardness: 1
Density: 3.576 g/cm³
Colors: Bronze red
Streak: Black
Luster: Metallic, strong
Transparency: Opaque
Crystal system: Hexagonal
Crystal habit: Scaly, thin
Cleavage: Good
Rarity: Rare
Uses: Collector
Host rock: As thin scales in the Kokka serpentine and in carbonate; rarely in chrysotile

Where rockhounds find haapalaite

Classic worldwide localities

Kokka serpentinite body, about 33 km north-northwest from the Outokumpu mine, Tapiola, Finland (type locality)

Field-hunting tip

Where it forms: As thin scales in the Kokka serpentine and in carbonate; rarely in chrysotile. If you start seeing pentlandite, maucherite, chalcopyrite in float, you are in the right ground. Typical habit: scaly, thin. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify haapalaite?+

Mohs hardness is 1. Luster: metallic, strong. The streak is black. Common colors include bronze red.

Where is haapalaite found?+

Notable localities include Kokka serpentinite body, about 33 km north-northwest from the Outokumpu mine, Tapiola, Finland (type locality).

Is haapalaite safe to handle?+

Haapalaite contains nickel. Wash your hands afterwards, never grind or breathe the dust, and store it apart from specimens you handle often.

What rocks look like haapalaite?+

Haapalaite is most often confused with Valleriite, Pyrrhotite, Pentlandite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with haapalaite?+

Haapalaite commonly co-occurs with Pentlandite, Maucherite, Chalcopyrite, Magnetite, Chromite, Lizardite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does haapalaite form in?+

Where it forms: As thin scales in the Kokka serpentine and in carbonate; rarely in chrysotile. Working float back to the host body is the standard way to chase a fresh occurrence.

What is haapalaite used for?+

Haapalaite is used in collector.

Find haapalaite on the map

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