We found 2-billion-year-old 'fingerprints' of life perfectly preserved inside industrial metal deposits.
April 2, 2026
Original Paper
Nickel Isotope Systematics in the Talvivaara Paleoproterozoic Black Shale Deposit Reveal Mineralogy-Controlled Fractionation with a Preserved Biogenic Signal
EarthArXiv · 10.31223/X5Q47Z
The Takeaway
It was previously assumed that the intense heat and geological pressure required to form metamorphic rocks would erase any trace of ancient biology. This study discovered that nickel isotopes in 2-billion-year-old shale still carry distinct biogenic signatures, effectively turning industrial ore into a time capsule of Earth's earliest organisms.
From the abstract
Nickel isotope systematics in sediment-hosted sulfide deposits are now more commonly used to infer redox and diagenetic processes, yet their potential to record biological signals and their preservation through diagenesis and metamorphism remains poorly constrained. Here we present micro-scale coupled δ60Ni, δ34S, δ13C, REE pattern, and paleoproductivity proxy data from the Paleoproterozoic Talvivaara Ni-Zn-Cu-Co deposit, a ~2.1-1.9 Ga black shale associated with the Shunga Event at the end of t