Ferrotochilinite is a rare, complex sulfide-hydroxide mineral belonging to the tochilinite group, typically found as microscopic platy or foliated aggregates. It is characterized by its metallic luster and black color, often occurring as an alteration product within serpentinized rocks associated with magnetite. Due to its scarcity, it is primarily sought after by advanced mineral collectors focusing on rare sulfide species.

Hardness

1-2

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrareTochilinite group family

Ferrotochilinite

Hardness: 1-2
Luster: Metallic
Streak: Black
Transparency: Opaque

No image

Is this ferrotochilinite?

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 ferrotochilinite with a known reference. Ferrotochilinite sits at Mohs 1-2 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Ferrotochilinite leaves a black streak.
3
Read the luster
Hold the specimen under a strong light. Ferrotochilinite typically shows a metallic luster.
4
Match the color range
Compare against the expected color range: black.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: platy crystals or massive aggregates.

Often confused with

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

Often found alongside ferrotochilinite

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

All properties

Chemical formula: Fe₅₊ₓS₆(Mg,Fe,Ni)₉(OH)₁₈
Mohs hardness: 1-2
Density: 3.3-3.4 g/cm³
Colors: Black
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Monoclinic
Crystal habit: Platy Crystals or Massive Aggregates
Cleavage: Perfect Basal
Rarity: Rare
Uses: Collector
Host rock: Serpentinized Ultramafic Rocks and Skarn Deposits
Typical price: $50-200 per specimen

Where rockhounds find ferrotochilinite

Classic worldwide localities

Korshunovskoye iron deposit, Russia
Kovdor, Kola Peninsula, Russia
Chrysotile deposits, Canada

Field-hunting tip

Look in serpentinized ultramafic rocks and skarn deposits country — that is the host setting where ferrotochilinite typically forms. If you start seeing magnetite, serpentine, calcite in float, you are in the right ground. Field specimens usually show a platy crystals or massive aggregates habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify ferrotochilinite?+

Mohs hardness is 1-2. It typically shows a metallic luster. The streak is black. Common colors include black.

Where is ferrotochilinite found?+

Notable localities include Korshunovskoye iron deposit, Russia; Kovdor, Kola Peninsula, Russia; Chrysotile deposits, Canada.

How much is ferrotochilinite worth?+

Typical asking prices fall in the range of $50-200 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like ferrotochilinite?+

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

What minerals are found with ferrotochilinite?+

Ferrotochilinite commonly co-occurs with Magnetite, Serpentine, Calcite, Pyrite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does ferrotochilinite form in?+

Ferrotochilinite typically forms in serpentinized ultramafic rocks and skarn deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is ferrotochilinite used for?+

Ferrotochilinite is used in collector.

Find ferrotochilinite on the map

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