Acasta Gneiss

The Acasta Gneiss is one of Earth's oldest known rocks, dating back about 4.03 billion years. Located in Canada's Northwest Territories, it is a type of metamorphic rock that has been heavily altered by heat and pressure over billions of years. Its ancient age provides valuable insights into Earth's early history and the formation of its crust. The Acasta Gneiss is significant because it represents some of the earliest solid evidence of continental crust, helping scientists understand how our planet evolved in its infancy.