Calculating the age of the Earth, and so pinpointing the moment of Creation, has been a theological and scientific preoccupation for centuries. A memorable attempt to provide a beginning for everything was made in the mid-17th century by James Ussher (1581-1656), Archbishop of Armagh, who claimed that Creation fell precisely on Sunday 23 October, 4004 BC.

What was eventually revealed was a far larger expanse of geological time than the Bible would account for. Evidence of this deep time is locked into the rocks of the Earth itself. By the early 20th century, radioactive dating techniques refined estimates of the age of the Earth, currently calculated at about 4.54 billion years.

This meteorite, which fell at Rewari, India in 1929, comes from the belt of asteroids orbiting the Sun between Mars and Jupiter. At about 4.54 billion years old, it is the same age as the Earth itself.
Radiometric dating shows that this gneiss, from West Greenland, is about 3.75 billion years old, making it one of the oldest rocks on Earth.