Hapkeite is an extremely rare iron silicide mineral first discovered within lunar meteorites. It typically occurs as microscopic inclusions within the fusion crust or regolith of meteorites and is characterized by its distinct metallic luster and cubic structure.

Hardness

5.5

Mohs

Luster

Metallic

Transparency

Opaque

mineralrare

Hapkeite

Hardness: 5.5
Luster: Metallic
Transparency: Opaque

No image

Is this hapkeite?

4-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 hapkeite with a known reference. Hapkeite sits at Mohs 5.5, softer than the next harder reference, harder than the previous one.
2
Read the luster
Hold the specimen under a strong light. Luster: metallic.
3
Match the color range
Compare against the expected color range: yellowish white.
4
Look at form & habit
Crystal system: cubic. Typical habit: microscopic crystals.

Often confused with

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

mineral

Iron

Mohs 4

How to tell apart: Hapkeite is noticeably harder (Mohs 5.5 vs. 4).

All properties

Chemical formula: Fe₂Si
Mohs hardness: 5.5
Density: 6.83 g/cm³
Colors: Yellowish white
Luster: Metallic
Transparency: Opaque
Crystal system: Cubic
Crystal habit: Microscopic crystals
Rarity: Rare
Uses: Collector
Host rock: In a highland regolith breccia clast in the lunar meteorite Dhofar 280, formed by impact-induced, vapor-phase deposition under extreme reducing conditions in lunar soil

Where rockhounds find hapkeite

Classic worldwide localities

Lunar meteorite Dhofar 280 collected in Dhofar Province (Al Janubiyah Province), Oman

Field-hunting tip

Where it forms: In a highland regolith breccia clast in the lunar meteorite Dhofar 280, formed by impact-induced, vapor-phase deposition under extreme reducing conditions in lunar soil. If you start seeing fesi, vitrified plagioclase, feni in float, you are in the right ground. Typical habit: microscopic crystals. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify hapkeite?+

Mohs hardness is 5.5. Luster: metallic. Common colors include yellowish white.

Where is hapkeite found?+

Notable localities include Lunar meteorite Dhofar 280 collected in Dhofar Province (Al Janubiyah Province), Oman.

What rocks look like hapkeite?+

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

What minerals are found with hapkeite?+

Hapkeite commonly co-occurs with FeSi, Vitrified plagioclase, FeNi. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does hapkeite form in?+

Where it forms: In a highland regolith breccia clast in the lunar meteorite Dhofar 280, formed by impact-induced, vapor-phase deposition under extreme reducing conditions in lunar soil. Working float back to the host body is the standard way to chase a fresh occurrence.

What is hapkeite used for?+

Hapkeite is used in collector.

Find hapkeite on the map

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