Earth’s core could contain helium from the early solar system. The noble gas tucks into gaps in iron crystals under high pressure and temperature.

Numerous iron-containing minerals exist on Earth (Table 1 & Figure 2 ... Journal of Plant Nutrition & Soil Science 168, 558–-573 (2005). Behrenfeld, M. J. & Kolber, Z. S.

A team of geologists has unveiled the largest iron ore ... This table highlights the sheer magnitude of the deposit and its transformative implications for both science and the economy.

The extraction of iron, which led ... this century will be. The table below sets out the time-scale of some of the major events in Earth history and developments in science and technology.