Craton is a geological term referring to an old and stable portion of a continental plate that has been relatively undisturbed from the Precambrian era. The area forms the nuclear mass of a continent, or the central basin of an ocean. The term includes both shield and platform layers. Cratons can be areas of economic importance, as diamonds and precious metals can be found in their depths. As one example, the Slave craton in Nunavut, Canada, is currently the centre of a slew of penny stock mining companies, hoping to find diamonds and gold and the like.
The name is derived from the Greek kratos. One pronunciation guide has the word pronounced 'krA-"tän