Stannoidite is a rare copper-iron-tin sulfide mineral typically found in hydrothermal vein deposits. It is often identified by its distinct bronze color and metallic luster, usually occurring as massive grains rather than well-formed crystals.

Hardness

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrare

Stannoidite

Hardness: 4
Luster: Metallic
Streak: Black
Transparency: Opaque

Is this stannoidite?

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 stannoidite with a known reference. Stannoidite sits at Mohs 4 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Stannoidite leaves a black streak.
3
Read the luster
Hold the specimen under a strong light. Stannoidite typically shows a metallic luster.
4
Match the color range
Compare against the expected color range: bronze, brown, black.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: massive, anhedral grains.

Often confused with

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

Often found alongside stannoidite

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

All properties

Chemical formula: Cu₈Fe₃Sn₂S₁₂
Mohs hardness: 4
Density: 4.45 g/cm³
Colors: Bronze Brown Black
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Orthorhombic
Crystal habit: Massive, Anhedral Grains
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Hydrothermal Tin-copper Vein Deposits
Typical price: $50-300 per specimen

Where rockhounds find stannoidite

Classic worldwide localities

Suzuyama mine, Japan
Ikuno mine, Japan
Toroku mine, Japan
Broken Hill, Australia

Field-hunting tip

Look in hydrothermal tin-copper vein deposits country — that is the host setting where stannoidite typically forms. If you start seeing stannite, chalcopyrite, sphalerite in float, you are in the right ground. Field specimens usually show a massive, anhedral grains habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify stannoidite?+

Mohs hardness is 4. It typically shows a metallic luster. The streak is black. Common colors include bronze, brown, black.

Where is stannoidite found?+

Notable localities include Suzuyama mine, Japan; Ikuno mine, Japan; Toroku mine, Japan; Broken Hill, Australia.

How much is stannoidite 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 stannoidite safe to handle?+

It contains toxic constituents. Contains copper, iron, tin, and sulfur; handle with care and wash hands after handling to avoid ingestion or skin irritation. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like stannoidite?+

Stannoidite is most often confused with Stannite, Briartite, Germanite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with stannoidite?+

Stannoidite commonly co-occurs with Stannite, Chalcopyrite, Sphalerite, Cassiterite, Bornite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does stannoidite form in?+

Stannoidite typically forms in hydrothermal tin-copper vein deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is stannoidite used for?+

Stannoidite is used in collector.

Find stannoidite on the map

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