How old is Stone Mountain around the suburbs of Atlanta Georgia?

Stone Mountain is estimated to be around 300 million years old. It is composed of granite, which is an igneous rock that forms when molten rock cools and solidifies. The granite that makes up Stone Mountain was formed during the late Paleozoic era, when the area was subjected to intense heat and pressure. Over time, the granite has eroded and weathered to form the distinctive dome-shaped mountain that we see today.