Apuanite is a rare antimony-iron sulfide-oxide mineral discovered in the mining districts of the Apuan Alps. It is typically found as small, black, metallic tabular crystals occurring alongside other rare antimony species like versiliaite.

Hardness

5-6

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrare

Apuanite

Hardness: 5-6
Luster: Metallic
Streak: Black
Transparency: Opaque

Is this apuanite?

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 apuanite with a known reference. Apuanite sits at Mohs 5-6 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Apuanite leaves a black streak.
3
Read the luster
Hold the specimen under a strong light. Apuanite typically shows a metallic luster.
4
Match the color range
Compare against the expected color range: black, brownish-black.
5
Look at form & habit
Crystal system: tetragonal. Typical habit: tabular crystals.

Often confused with

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

mineral

Versiliaite

Mohs 3.5

How to tell apart: Apuanite is noticeably harder (Mohs 5-6 vs. 3.5).

How to tell apart: Streak differs — Apuanite leaves black, Derbylite leaves brown; luster reads metallic on Apuanite and submetallic on Derbylite.

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Often found alongside apuanite

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

All properties

Chemical formula: Fe²⁺₄Sb³⁺₄O₁₂S
Mohs hardness: 5-6
Density: 5.32 g/cm³
Colors: Black Brownish-black
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Tetragonal
Crystal habit: Tabular Crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Hydrothermal Veins in Marble
Typical price: $50-300 per specimen

Where rockhounds find apuanite

Classic worldwide localities

Apuan Alps, Tuscany, Italy

Field-hunting tip

Look in hydrothermal veins in marble country — that is the host setting where apuanite typically forms. If you start seeing versiliaite, derbylite, cinnabar in float, you are in the right ground. Field specimens usually show a tabular crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify apuanite?+

Mohs hardness is 5-6. It typically shows a metallic luster. The streak is black. Common colors include black, brownish-black.

Where is apuanite found?+

Notable localities include Apuan Alps, Tuscany, Italy.

How much is apuanite worth?+

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

Is apuanite safe to handle?+

It contains toxic constituents. Contains antimony, a toxic heavy metal. Wash hands thoroughly after handling and avoid inhaling dust. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like apuanite?+

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

What minerals are found with apuanite?+

Apuanite commonly co-occurs with Versiliaite, Derbylite, Cinnabar, Pyrite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does apuanite form in?+

Apuanite typically forms in hydrothermal veins in marble. Working float back to the host body is the standard way to chase a fresh occurrence.

What is apuanite used for?+

Apuanite is used in collector.

Find apuanite on the map

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