The Pilbara craton is one of the few areas with crust from the Archean eon. The Apex cherts, dated at 3.465-3.458 billion years old, are in the Warrawoona Group from the eastern part of this region. Studies show that the Warrawoona Group cherts were deposited in a variety of environments ranging from mid-oceanic spreading to converging tectonic plate boundaries via a hotspot. Image Credit: Wikimedia Commons, Hesperian