How do I identify Pyroxferroite?

Pyroxferroite can be identified by its hardness of 4.5 - 5.5 on the Mohs scale, Pale yellow color. Look for these key characteristics when examining specimens.

What color is Pyroxferroite?

Pyroxferroite typically appears in Pale yellow, orange-yellow, yellow, light brown. Color can vary depending on impurities and formation conditions.

How hard is Pyroxferroite?

Pyroxferroite has a hardness of 4.5 - 5.5 on the Mohs scale. This gives it moderate hardness.

Pyroxferroite

A variety of Minerals

What is Pyroxferroite?

Pyroxferroite (Fe,Ca)SiO3 is a single chain inosilicate. It is mostly composed of iron, silicon and oxygen, with smaller fractions of calcium and several other metals. Together with armalcolite and tranquillityite, it is one of the three minerals which were discovered on the Moon. It was then found in Lunar and Martian meteorites as well as a mineral in the Earth's crust. Pyroxferroite can also be produced by annealing synthetic clinopyroxene at high pressures and temperatures. The mineral is metastable and gradually decomposes at ambient conditions, but this process can take billions of years.

Pyroxferroite Market Value Calculator

Estimate the market value of Pyroxferroite using size, quality, and finish. This preview calculator is for quick context and is not a formal appraisal.

Pyroxferroite Localities Map

See where Pyroxferroite is found with a localities map, collecting zones, and geology context. Generate a sample map preview below.

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North ZoneCentral RidgeSouth Basin

Key Characteristics

Characteristics of Pyroxferroite

The crystal structure of pyroxferroite contains silicon-oxygen chains with a repeat period of seven SiO4 tetrahedra. These chains are separated by polyhedra where a central metal atom is surrounded by 6 or 7 oxygen atoms; there are 7 inequivalent metal polyhedra in the unit cell. The resulted layers are parallel to (110) planes in pyroxferroite, whereas they are parallel to (100) planes in pyroxenes. Chemical composition of pyroxferroite can be decomposed into elementary oxides as follows: FeO (concentration 44–48%), SiO2(45–47%), CaO (4.7–6.1%), MnO (0.6–1.3%), MgO (0.3-1%), TiO2 (0.2–0.5%) and Al2O3 (0.2–1.2%). Whereas magnesium is usually present at about 0.8%, in some samples it had an undetectably low concentration.

Formation of Pyroxferroite

Pyroxferroite was first discovered in 1969 in lunar rock samples from the Sea of Tranquility during the Apollo missions. Together with armalcolite and tranquillityite, it is one of the three minerals which were first found on the Moon. Later, pyroxferroite was detected in Lunar and Martian meteorites recovered in Oman. It also occurs in the Earth's crust, in association with clinopyroxene, plagioclase, ilmenite, cristobalite, tridymite, fayalite, fluorapatite and potassic feldspar, and forms series with pyroxmangite. Pyroxferroite has been found in the Isanago mine, in Kyoto Prefecture, Japan; near Iva, Anderson County, South Carolina, USA; from Väster Silfberg, Värmland, Sweden; and Lapua, Finland. In the original lunar samples, pyroxferroite was associated with similar minerals, but also with troilite which is rare on Earth, but is common on the Moon and Mars.