Kushiroite is a rare mineral of the pyroxene group, with formula CaAlAlSiO₆. It is the fully aluminian member. The formula of kushiroite corresponds to the molecule (or component) known as Calcium-Tschermak (Ca-Tschermak), which dominates in the composition of kushiroite. Kushiroite is an

aluminium Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. I ...

-analogue of other pyroxene-group members,

davisite Davisite is an exceedingly rare mineral of the pyroxene group, with formula CaScAlSiO6. It is the scandium-dominant member.Mindat, http://www.mindat.org/min-38829.html It stands for scandium-analogue of other pyroxene-group members, esseneite, gros ...

esseneite Esseneite is a relative rare mineral of the pyroxene group, with formula CaFeAlSiO6. It is the ferric-iron-dominant member. Esseneite is an iron-analogue of other pyroxene-group members, davisite, grossmanite, and kushiroite. It is a metamorphic ...

, and

grossmanite Grossmanite is a very rare mineral of the pyroxene group,Mindat, Grossmanite, http://www.mindat.org/min-39426.html with formula CaTi3+AlSiO6. It is the titanium-dominant member. Grossmanite is unique in being a mineral with trivalent titanium, a fea ...

. It was found in a chondrite meteorite within refractory inclusions. The mineral crystallizes in the

monoclinic crystal system In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in the orthorhombic sy ...

(space group ''C2/c'').

References

Pyroxene group Inosilicates Calcium minerals Aluminium minerals Monoclinic minerals Minerals in space group 15 {{silicate-mineral-stub