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-analogue of other pyroxene-group members, davisite, esseneite, and grossmanite. It was found in a chondrite meteorite within refractory inclusions.
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Kushiroite Wikipedia(Text) CC BY-SA