Magnetite
“Earth's natural magnet”
Mineral
Magnetite is an iron oxide mineral and the most magnetic naturally occurring mineral on Earth. It played a crucial role in the history of navigation, as lodestone — a naturally magnetized form of magnetite — was used to create the first magnetic compasses.
Composition
iron oxide (Fe₃O₄)
Where Found
Kiruna (Sweden), Adirondacks (USA), Ural Mountains (Russia), Bushveld (South Africa)
Mohs Hardness
5.5-6.5
Fun Fact
Some bacteria and animals, including pigeons and sea turtles, have tiny magnetite crystals in their bodies that may help them navigate using Earth's magnetic field.
Test Your Knowledge
How do geologists use magnetite grains in ancient rocks to reconstruct past plate movements?
Related Specimens
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