A chip of zircon found in Western Australian rocks at a place called North Pole Dome revealed the age of Earth's oldest known impact crater. The team that found it was working on age-dating the crater, which is located in a region called the Pilbara Craton. They used mineral dating to pinpoint the exact time it was dug out by an impactor. Team lead Chris Kirkland from the Timescales of Minerals Systems Group within Curtin University's School of Earth and Planetary Sciences, said the findings help resolve a longstanding question about the timing of the impact. The results of the team's analysis of several minerals at the site, along with zircon, indicated that the North Pole Dome impact occurred at 3.024 billion years ago (plus or minus a few million years).