Pyroxferroite is a rare pyroxenoid mineral best known for its discovery in lunar basalt samples brought back by the Apollo 11 mission. It typically occurs as small brown to amber grains in iron-rich igneous or metamorphic environments and is a distinct high-pressure polymorph of iron silicate.

Hardness

5.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrarePyroxenoid Group family

Pyroxferroite

Hardness: 5.5
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this pyroxferroite?

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 pyroxferroite with a known reference. Pyroxferroite sits at Mohs 5.5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Pyroxferroite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Pyroxferroite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: brown, amber, tan.
5
Look at form & habit
Crystal system: triclinic. Typical habit: tabular crystals, massive, granular.

Often confused with

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

Often found alongside pyroxferroite

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

All properties

Chemical formula: (Fe,Ca)SiO₃
Mohs hardness: 5.5
Density: 3.8-3.9 g/cm³
Colors: Brown Amber Tan
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Triclinic
Crystal habit: Tabular Crystals, Massive, Granular
Cleavage: Good in Two Directions
Rarity: Rare
Uses: Collector, Scientific Research
Host rock: Lunar Basalt, Metamorphic Rocks
Typical price: $50-500 depending on specimen size and source

Where rockhounds find pyroxferroite

Classic worldwide localities

Moon (Apollo 11 mission samples)
Sweden
Scotland
Japan

Field-hunting tip

Look in lunar basalt, metamorphic rocks country — that is the host setting where pyroxferroite typically forms. If you start seeing plagioclase, ilmenite, cristobalite in float, you are in the right ground. Field specimens usually show a tabular crystals, massive, granular habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify pyroxferroite?+

Mohs hardness is 5.5. It typically shows a vitreous luster. The streak is white. Common colors include brown, amber, tan.

Where is pyroxferroite found?+

Notable localities include Moon (Apollo 11 mission samples); Sweden; Scotland; Japan.

How much is pyroxferroite worth?+

Typical asking prices fall in the range of $50-500 depending on specimen size and source. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like pyroxferroite?+

Pyroxferroite is most often confused with Pyroxmangite, Rhodonite, Ferrosilite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with pyroxferroite?+

Pyroxferroite commonly co-occurs with Plagioclase, Ilmenite, Cristobalite, Fayalite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does pyroxferroite form in?+

Pyroxferroite typically forms in lunar basalt, metamorphic rocks. Working float back to the host body is the standard way to chase a fresh occurrence.

What is pyroxferroite used for?+

Pyroxferroite is used in collector, scientific research.

Find pyroxferroite on the map

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