Earth’s largest iron ore deposits exposed a 1.3-billion-year-old secret to geologists

By Eric Ralls – earth.com

Steel is the skeleton of modern life, yet the iron that makes it has a backstory far older than the first nail. For decades, geologists thought the world’s richest and largest iron ore deposits formed not long after breathable oxygen spread through Earth’s air some 2.2 billion years ago.

Fresh evidence now knocks that timing sideways, suggesting the world-class reserves in the Pilbara’s Hamersley Province of Australia are about 1.4 to 1.1 billion years younger than previously believed.