Grossite is a calcium aluminium oxide mineral with formula CaAl4O7.

It was named for Shulamit Gross (1923–2012) of the Geological Survey of Israel.

[2][4] It occurs within high temperature metamorphosed impure limestone of the Hatrurim Formation and also within calcium-aluminium rich inclusions in chondritic meteorites.

Associated minerals in the Hatrurium include brownmillerite, mayenite and larnite.

In meteorites it occurs with perovskite, melilite, hibonite, spinel and calcium rich pyroxene.