Overview
- Researchers reported on Thursday that a carbon‑rich chert from Bhitardari in the Singhbhum Craton contains layered carbon and silica and returned a uranium–lead zircon age of about 3.497 billion years.
- U–Pb dating was performed on tiny zircon crystals found inside the same chert, and the team argues those volcanic zircons formed as the deposit accumulated, giving a direct age for the rock.
- Multiple laboratory tests including Raman spectroscopy and carbon‑isotope measurements found the carbon to be strongly enriched in 12C and to have a heat and structural history consistent with original organic material.
- The rock’s repeating thin bands of silica and carbon are interpreted by the authors as fossilized microbial mats laid down in an iron‑ and silica‑rich underwater hydrothermal setting that could supply chemical energy for early life.
- The paper’s authors and coverage stress that independent dating, petrographic work and geochemical replication are needed before the claim is settled, and they place the find alongside earlier disputed early‑life reports from Greenland, Australia, South Africa and Canada.