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, 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.