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.[1][2] 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.[4]