Sugakiite is a rare copper-iron sulfide mineral typically found in intimate intergrowths within skarn-type ore deposits. It is primarily identified in polished sections via microscopic examination due to its extremely small grain size and similarity to other copper-iron sulfides.

Hardness

2-3

Mohs

Luster

Metallic

Transparency

Opaque

mineralrare

Sugakiite

Hardness: 2-3
Luster: Metallic
Transparency: Opaque

No image

Is this sugakiite?

4-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 sugakiite with a known reference. Sugakiite sits at Mohs 2-3, softer than the next harder reference, harder than the previous one.
2
Read the luster
Hold the specimen under a strong light. Luster: metallic.
3
Match the color range
Compare against the expected color range: reddish yellow.
4
Look at form & habit
Crystal system: tetragonal. Typical habit: granular.

Often confused with

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

Often found alongside sugakiite

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

All properties

Chemical formula: Cu(Fe,Ni)₈S₈
Mohs hardness: 2-3
Density: 4.71 g/cm³
Colors: Reddish yellow
Luster: Metallic
Transparency: Opaque
Crystal system: Tetragonal
Crystal habit: Granular
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: An intergranular exsolved phase in sulfide aggregates in lherzolite in a peridotite massif

Where rockhounds find sugakiite

Classic worldwide localities

Horoman peridotite massif, Samanicho, Samani-gun, Hokkaido, Japan

Field-hunting tip

Where it forms: An intergranular exsolved phase in sulfide aggregates in lherzolite in a peridotite massif. If you start seeing bornite, talnakhite, copper in float, you are in the right ground. Typical habit: granular. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify sugakiite?+

Mohs hardness is 2-3. Luster: metallic. Common colors include reddish yellow.

Where is sugakiite found?+

Notable localities include Horoman peridotite massif, Samanicho, Samani-gun, Hokkaido, Japan.

Is sugakiite safe to handle?+

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

What rocks look like sugakiite?+

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

What minerals are found with sugakiite?+

Sugakiite commonly co-occurs with Bornite, Talnakhite, Copper. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does sugakiite form in?+

Where it forms: An intergranular exsolved phase in sulfide aggregates in lherzolite in a peridotite massif. Working float back to the host body is the standard way to chase a fresh occurrence.

What is sugakiite used for?+

Sugakiite is used in collector.

Find sugakiite on the map

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