8.25" Strelley Pool Stromatolite Slab - 3.43 Billion Years Old
There has been claims that the 30 million year older Apex Chert contained older trace fossils, but in 2015 further studies concluded that these "trace fossils" were in fact created by minerals forming in hydrothermal systems.
These oxygen producing cyanobacteria were so simple they lacked DNA packaging nucleus, but were responsible for possibly the largest changes the earth has undergone. They were the only major source of atmospheric oxygen critical for the development of more complex life.
Please note: Australia has export laws governing the export of all fossils. These specimens were exported legally with appropriate permits.