Zechstein Sea. Fossils are a series of epoxy resin and salt casts in which are embedded data storage media – taken from successive generations of computers and phones – and items related to my personal memory: my mother’s lip pencil, the syringe with oxytocin that I was given before my daughter’s birth, and the hospital ID ankle bracelet from when she was born. The salt slowly works inside the cast: the objects undergo changes because salt breaks down other chemical compounds, leading to their decomposition into component ions. The Fossils are associated with the mother project Zechstein Sea, a column of salt which was excavated from the Kłodawa salt mine in the Greater Poland Voivodeship. The 250-million-year-old salt was formed from the Zechstein Sea, an epicontinental sea that stretched from the lowland areas of Great Britain to northern and central Poland during the late Permian period. At that time, the area was near the equator and, due to the high temperatures and arid conditions, the sea evaporated. Its eventual disappearance was part of a general marine regression that preceded and accompanied the Permian-Triassic extinction, the largest extinction event in Earth’s history, when the global sea level fell 250 metres.