Maoniupingite-(Ce)
Maoniupingite-(Ce) is an IMA-recognized mineral species in the silicate class, with the chemical formula (Ce,Ca)₄(Fe³⁺,Ti,Fe²⁺, )(Ti,Fe³⁺,Fe²⁺,Nb)₄Si₄O₂₂.
It crystallizes in the monoclinic crystal system (space group C2/m). It is a member of the Chevkinite structural group.
Key properties: Mohs hardness 72.2–89.2; specific gravity 4.62; Black streak; Submetallic luster.
IMA symbol Mao-Ce, IMA status: approved, named in 2003.
Found in fractures in lamprophyre veins and along the contact between lamprophyre and a later quartz-alkali feldspar syenite dike with REE mineralization.
It is found associated with Microcline, albite, quartz, iron-rich phlogopite, augite, muscovite, calcite, baryte, fluorite, epidote, pyrite, magnetite, hematite, galena, hydroxylapatite.
The name refers to the occurrence near the Maoniuping REE deposit, China.