Heideite is an extremely rare iron-chromium-titanium sulfide found almost exclusively in the Bustee enstatite achondrite meteorite. Collectors rarely encounter this mineral, which typically occurs as tiny inclusions within extraterrestrial silicate matrices.

Hardness

3.5-4.5

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrare

Heideite

Hardness: 3.5-4.5
Luster: Metallic
Streak: Black
Transparency: Opaque

Is this heideite?

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 heideite with a known reference. Heideite sits at Mohs 3.5-4.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Streak: black.
3
Read the luster
Hold the specimen under a strong light. Luster: metallic.
4
Match the color range
Compare against the expected color range: steel gray.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: anhedral grains.

Often confused with

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

mineral

Troilite

Mohs 3.5-4.5

How to tell apart: Streak differs, so Heideite leaves black, Troilite leaves dark grayish brown.

How to tell apart: Streak differs, so Heideite leaves black, Daubréelite leaves brown.

Compare →

Often found alongside heideite

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

All properties

Chemical formula: (Fe,Cr,Ti)₁.₈₅S₂
Mohs hardness: 3.5-4.5
Density: 3.942 g/cm³
Colors: Steel gray
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Monoclinic
Crystal habit: Anhedral grains
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: As minute anhedral grains (Bustee meteorite)

Where rockhounds find heideite

Classic worldwide localities

Bustee enstatite achondrite meteor (type locality)

Field-hunting tip

Where it forms: As minute anhedral grains (Bustee meteorite). If you start seeing titanian troilite, ferroan alabandite, daubréelite in float, you are in the right ground. Typical habit: anhedral grains. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify heideite?+

Mohs hardness is 3.5-4.5. Luster: metallic. The streak is black. Common colors include steel gray.

Where is heideite found?+

Notable localities include Bustee enstatite achondrite meteor (type locality).

What rocks look like heideite?+

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

What minerals are found with heideite?+

Heideite commonly co-occurs with Titanian troilite, Ferroan alabandite, Daubréelite, Oldhamite, Osbornite, Niningerite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does heideite form in?+

Where it forms: As minute anhedral grains (Bustee meteorite). Working float back to the host body is the standard way to chase a fresh occurrence.

What is heideite used for?+

Heideite is used in collector.

Find heideite on the map

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