Fletcherite is a rare copper-nickel sulfide mineral member of the linnaeite group. It is primarily found in the Viburnum Trend of Missouri, often occurring as dark, metallic-lustered octahedrons associated with base-metal sulfides.

Hardness

4.5

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrareLinnaeite Group family

Fletcherite

Hardness: 4.5
Luster: Metallic
Streak: Black
Transparency: Opaque

Is this fletcherite?

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 fletcherite with a known reference. Fletcherite sits at Mohs 4.5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Fletcherite leaves a black streak.
3
Read the luster
Hold the specimen under a strong light. Fletcherite typically shows a metallic luster.
4
Match the color range
Compare against the expected color range: black, gray.
5
Look at form & habit
Crystal system: cubic. Typical habit: octahedral crystals, massive.

Often confused with

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

How to tell apart: Streak differs — Fletcherite leaves black, Polydymite leaves dark gray.

Compare →

Often found alongside fletcherite

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

All properties

Chemical formula: CuNi₂S₄
Mohs hardness: 4.5
Density: 4.8 g/cm³
Colors: Black Gray
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Cubic
Crystal habit: Octahedral Crystals, Massive
Cleavage: None
Rarity: Rare
Uses: Collector, Research
Host rock: Sedimentary-hosted Lead-zinc-copper Deposits
Typical price: $50-300 per specimen

Where rockhounds find fletcherite

Classic worldwide localities

Fletcher mine, Missouri, USA
Viburnum Trend, Missouri, USA

Field-hunting tip

Look in sedimentary-hosted lead-zinc-copper deposits country — that is the host setting where fletcherite typically forms. If you start seeing galena, chalcopyrite, sphalerite in float, you are in the right ground. Field specimens usually show a octahedral crystals, massive habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify fletcherite?+

Mohs hardness is 4.5. It typically shows a metallic luster. The streak is black. Common colors include black, gray.

Where is fletcherite found?+

Notable localities include Fletcher mine, Missouri, USA; Viburnum Trend, Missouri, USA.

How much is fletcherite 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 fletcherite safe to handle?+

It contains toxic constituents. Contains sulfur and heavy metals; avoid ingestion, inhalation of dust, or prolonged skin contact. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like fletcherite?+

Fletcherite is most often confused with Linnaeite, Carrollite, Polydymite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with fletcherite?+

Fletcherite commonly co-occurs with Galena, Chalcopyrite, Sphalerite, Pyrite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does fletcherite form in?+

Fletcherite typically forms in sedimentary-hosted lead-zinc-copper deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is fletcherite used for?+

Fletcherite is used in collector, research.

Find fletcherite on the map

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