5.3" Horodyskia Fossil Slab - Oldest Known Multicellular Life

This is a slab of 1.4 billion year old fossils of Horodyskia williamsii from Western Australia. Technically fossil Metazoan (or Colonial Foraminiferan) they are currently considered to be the oldest known multicellular fossils. They look like a string of beads that are connected by a stolon. Given that there would be few nutrients in the water they were almost certainly photosynthetic like the stromatolites.

They entire slab is 5.3" wide and contains multiple chains of Horodyskia.