Primary occurrences of ruby, pink sapphire, sapphires of other colors, and spinel have been found in marbles in the Ural Mountains. This article describes one occurrence, at Kootchinskoye, in the southern Urals, as a model for others in the Ural Mountains. Study of Kootchinskoye also gives some guidelines for predicting other ruby deposits. Although at present, there is no commercial production in this area, it appears to have significant potential.
