The Khito-Ostrov corundum
deposit is located 9 km north of the settlement of Chupa.
Corundum disseminations are mainly distributed in marginal parts of anorthosite bodies in association with garnet of pyrope-almandine composition (rhodolite
) and amphibole. Corundum also replaces accessory kyanite in the staurolite-garnet-biotite-amphibole rock.
Corundum crystals from anorthosite have prismatic and, less often, bladed or barrel-like shapes. The colour is pink, grayish-pink, crimson, and, less often, scarlet. The crystals are up to 5 cm long and up to 3 cm in diameter. The corundum contains gas-liquid and solid inclusions.
Ref: E.Ya. Kievlenko, Geology of gems, 2003, p. 59