A sheep ranch in the remote Jack Hills region of western Australia has yielded a huge discovery -- tiny zircon crystals that scientists have now confirmed are the oldest known materials formed on Earth. A team of researchers used two different techniques to date the crystals, which were extracted in 2001 from a rock outcrop of sandstone that formed an ancient beach 3 billion years ago. According to their findings, published in the journal Nature Geoscience, the crystals are fragments of the Earth’s crust and date back some 4.4 billion years, just 100 million years after the formation of the planet itself.