A craton is an ancient part of the Earth's continental crust which has been more or less stable since Precambrian times. Cratons whose ancient rocks are widely exposed at the surface, often with relatively subdued relief, are known as shields. If the ancient rocks are largely overlain by a cover of younger rocks then the 'hidden' craton may be referred to as a platform.
Baltic Shield, part of the East European Craton; Fennoscandian Shield, the exposed Northwestern part of the Baltic Shield in Norway, Sweden and Finland (3.1 Ga)
Karelian Craton, part of the Fennoscandian Shield in Southeast Finland and KareliaRussia, (3.4 Ga)