Micrometeorites: Earth's daily influx of metallic and stone-iron grains from the Asteroid Belt and how to collect them with magnets
To the point
Gerald Legg notes that Earth is constantly showered by micrometeorites from the asteroid belt—up to about 300 tonnes daily—mostly iron-bearing, which can be collected with magnets and identified under a microscope by looking for spherical grains, though many collected particles come from other sources.
