A team of researchers from the University of Cambridge and the University of California made a discovery that disputes the previous use of zircon crystals as evidence of Earth’s magnetic field’s early development. Their paper, published in Proceedings of the National Academy of Sciences, describes the testing they conducted and the new discoveries they made about the magnetism of zircon crystal. The Unknown Beginning of Earth’s Magnetic Field Many scientists believe that Earth’s magnetic field played a pivotal role in making life possible on the planet because it protects the atmosphere from solar wind, but, it isn’t clear when the magnetic field first appeared. Learning the origin of Earth’s magnetic field could not only help scientists understand the planet, but could also help establish life somewhere else. The Case for Zircon Crystals Scientists discovered zircon crystals in the Jack Hills area of Western Australia.. The zircon crystal is the oldest rock fragment, being roughly 4.4 billion years old in 2001, to ever be found on Earth. The crystals even date further back than the solid core that produces today’s magnetic field (formed roughly 3.5 billion years ago). Meaning, the finding could prove that liquid cores can also produce strong magnetic fields. This discovery means the crystals could provide insight and evidence of the conditions of the forming planet. In regards to magnetism, the crystals aren’t magnetic themselves but instead contain magnetic minerals and other elements, suggesting they were magnetized by a planetary magnetic field. Debunking Zircon Crystals’ Abilities to Provide Evidence The research team from the University of Cambridge and the University of California discovered that the crystals have nano-sized holes, which appear to be a result of radiation damage. This damage allowed magnetite, a common iron oxide mineral, to gather in the holes. Magnetite retains magnetism for long periods of time if it isn’t exposed to temperatures above 550 degrees Celsius. This finding of holes suggests that the magnetism of the crystals may have developed after the crystals were formed, which makes them unsuitable as evidence for the existence of a magnetic field during the Earth’s formation.   Learn More About Magnetism in Science While scientists are now unable to use zircon crystals to understand the state of the Earth and its magnetic field at its creation, they are making discoveries every day to determine when the planetary magnetic field came into existence. For more information on break-through magnetic discoveries, browse through our magnet in the news section, sign up for our monthly newsletter, or contact us today with your questions.