Orthopyroxenite
![ALH 84001 is an extraterrestrial example of an orthopyroxenite. It is an achondrite meteorite from Mars.](/Images/godic/202501/31/ALH84001_meteorite_Smithsonian1116.jpg")
![This ternary diagram shows the orthopyroxenites as a function of olivine, clinopyroxene and orthopyroxene abundance.](/Images/godic/202501/31/Peridotite_Olivine-Orthopyroxene-Clinopyroxene_Orthopyroxenite_highlighted.svg1116.png")
Orthopyroxenite is an ultramafic and ultrabasic rock that is almost exclusively made from the mineral orthopyroxene, the orthorhombic version of pyroxene and a type of pyroxenite. It can have up to a few percent of olivine and clinopyroxene.
Orthopyroxenites can also occur on other planets. ALH 84001 is a Martian meteorite that can be classified as an orthopyroxenite. It is the only meteorite found with that composition and the only member of the Martian orthopyroxenite group of meteorites.